i.MX RT Crossover MCUs Knowledge Base

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Testing Boot times – Generating a bootable image Bootable Image Structure: The bootable image consists of: FlexSPI Configuration Block (FCB) Image Vector Table (IVT) Boot Data Device Configuration Data (DCD) Program image CSF, Certificates, and signatures (this stuff is optional and only comes with high-assurance boot I’ll briefly explain each below: FlexSPI Configuration Block (FCB) The FCB will configure the settings of the FlexSPI communication. It will establish how many ports will be used, what clock speed to run the FlexSPI controller at, etc. This is the first thing that happens, as everything else is stored in Flash memory. In order to read anything else, the flash must first be configured.  Image Vector Table (IVT)  The IVT is a table that tells the memory the addresses of where everything is stored. Boot Data The Boot Data contains pointers to the start address of the Memory. Device Configuration Data (DCD) The DCD contains configuration data to configure any peripherals. Program image The program image contains the code you write to go into the application. CSF, Certificates, and signatures These things are optional. They come with high-assurance boot sequence and will not be covered in this writeup. Below is a rough table outlining these different parts of the boot image: Bootable Image generation software / tools: MCUXpresso – download the MCUXpresso IDE Flash Loader – download from RT1050 page > software and tools > flashloader This entire folder will include the MFGTool, elftosb tool, and more documentation. DCD.bin file: I found mine included in this document: https://community.nxp.com/docs/DOC-340655 Bootable Image Generation Overview MCUXpresso can generate bootable images for Hyperflash and QSPI XiP, but if trying to boot and execute in place of SDRAM or intern SRAM, or from your own memory module, then you must generate a bootable image by through a combination of generating an s record or elf image on MCUXpresso, and then using the flashloader tool suite (elftosb and mfgtool) to create a bootable image and then a bootable program to upload to the board. The entire general process is described below. In subsequent sections, a more detailed step-by-step guide is provided for Hyperflash XiP, SDRAM, and SRAM, each. MCUXpresso Configurations and output: Begin with your application code in MCUXpresso. Change memory allocation in the memory configuration editor of the MCU Settings part of MCUXpresso according to where you would like to boot from. If applicable, be sure to specify in the preprocessor settings if you would like to enable the dcd in the boot image. Generate an s-record (.s19) file from MCUXpresso using binary utilities. Elftosb tool – .bin file generation You can find this tool in the flashloader. Call an imx command to it which will take as input the s-record file containing the program image, a dcd.bin file (may or may not be in the s-record), a FCB?, and a bd_file (given to you, specific to your memory configuration). The elftosb tool will generate as an output a .bin file. Elftosb tool – Bootable image generation Then call the elftosb tool again with a kinetis command. This will take the .bin file and convert it to a boot_image.sb file. MFG tool Then we can use the mfg tool to generate the program image for the board, and upload it. In order to do this, the board SW7 must be set to OFF-ON-OFF-ON, and switch the jumper from J1  (5-6) to J1 (3-4). Connect the USB cable to J9 to power the board. Then connect the board to your computer and run the Mfg tool. Click start and the image will be uploaded.      After this the bootable image will be uploaded to the board and you’ll be good to go! Remember to switch the pin headers back, so the board can boot normally. J1 (5-6) and SW7 to OFF-ON -ON -OFF to boot from Hyperflash. Now in the following sections I’ll break down specific examples of what to do depending on the specific memory location you’d like to boot from. Bootable Image Generation – XiP Hyperflash Please note that this can also be done in MCUXpresso, but In order to use my own dcd file, I did this project using the traditional flashloader tools.   MCUXpresso Configurations and output: Begin by changing memory allocation in the memory configuration editor (edit project settings >> C/C++ Build >> MCU settings >>edit. It should look like the one below. Then go to C/C++ Build >>settings > MCU C compiler > preprocessor and set the XIP_boot_header enable and and XIP_boot_header_DCD_enable both to 0 if you have a dcd.bin file to use. Otherwise set these fields to 1. Hit apply and close. Go to the debug portion and click on binary utilities, then generate an s-record (.s19) file from MCUXpresso.  Click build to re-build the project. Copy this .s19 file. Elftosb tool – .bin file generation In the flashloader tool, go to Tools > elftosb > Win, and drop the .s19 file in this folder, as well as the dcd.bin file. Fire up command prompt in administrator mode, and use command cd [elftosb directory] to get to this folder To generate the .bin file, call the command:   elftosb.exe -f imx -V -c ../../bd_file/imx10xx/imx-flexspinor-normal-unsigned-dcd.bd -o ivt_flexspi_nor_led_blinky.bin HYPERFLASH_led_blinky.s19   This command essentially uses the imx-flexspinor bd linker file to generate a .bin file that will include the dcd.bin header inside. Note that HYPERFLASH_led_blinky.s19 should be renamed to your actual file name acquired from MCUXpresso   Elftosb tool – Bootable image generation Then we must generate the boot_image.sb Then call the elftosb tool again with a kinetis command. This will take the .bin file and convert it to a boot_image.sb file. The command is:   elftosb.exe -f kinetis -V -c ../../bd_file/imx10xx/program_flexspinor_image_hyperflash.bd -o boot_image.sb ivt_flexspi_nor_led_blinky_nopadding.bin   Note: The output of the first imx command we made must match the input of this one (ivt_flexspi_nor_led_blinky_nopadding.bin). Also, the output must remain named boot_image.sb, otherwise it will not work. MFG tool Then we can use the mfg tool to generate the program image for the board, and upload it. In order to do this, the board SW7 must be set to OFF-ON-OFF-ON, and switch the jumper from J1  (5-6) to J1 (3-4). Connect the USB cable to J9 to power the board. Then connect the board to your computer and run the Mfg tool. Click start and the image will be uploaded.        Copy the boot_image.sb file that we created in the last step. Move it to the directory Tools > mfgtools-rel > Profiles > MXRT105X > OS Firmware, and drop it in here. Next, set SW7 on the board to OFF-ON-OFF-ON, and switch the jumper at the bottom to power the board. Then connect the USB cable to J9. This will allow you to program the board. Go back to the folder mfgtools-rel and Open the Mfg Tool. It should say HID- compliant vendor-defined device. Otherwise double check SW7 and the power pin at the bottom right.   Click start and if successful it should look like: Please note that this success only means that it was able to upload the bootable image to the board. This usually works well. However, if you find later that the board doesn’t do what it’s supposed to, then there might be a problem in the other steps of the processor. Check to make sure you used the right linker file, and that the settings in MCUXpresso are configured correctly. Press stop and exit Remember to switch the pin headers back, so the board can boot normally. J1 (5-6) and SW7 to OFF-ON -ON -OFF to boot from Hyperflash.   Bootable Image Generation – SDRAM The guide is based off this link: https://community.nxp.com/docs/DOC-340655 . Download the files provided there, and unzip. Everything is good except the first step of that pdf document is a little unclear. MCUXpresso Configurations and output: Begin by changing memory allocation in the memory configuration editor of the MCU Settings part of MCUXpresso. It should look like the one below. Then go to settings > MCU C compiler > preprocessor and set the XIP_boot_header enable and and XIP_boot_header_DCD_enable both to 0 Hit apply and close. Go to C/C++ Build >> Settings >> MCU Linker >> Manage linker script, and check the box Link application to RAM. Go to the debug portion and click on binary utilities, then generate an s-record (.s19) file from MCUXpresso.  Click build to re-build the project. You can check the console to verify the correct allocations of memory: Copy this .s19 file. Elftosb tool – .bin file generation In the flashloader tool, go to Tools > elftosb > Win, and drop the .s19 file in this folder, as well as the dcd.bin file. There’s another step for booting from SDRAM. Take the file imx-sdram-normal-unsigned-dcd.bd (included in the link posted) and drag it into Tools > bd_file > imx10xx Fire up command prompt in administrator mode, and use command cd [elftosb directory] to get to this folder To generate the .bin file, call the command:   elftosb.exe -f imx -V -c ../../bd_file/imx10xx/imx-sdram-normal-unsigned-dcd.bd -o evkbimxrt1050_led_blinky.bin SDRAM1_led_blinky.s19   This command essentially uses the imx-flexspinor bd linker file to generate a .bin file that will include the dcd.bin header inside. Note that HYPERFLASH_led_blinky.s19 should be renamed to your actual file name acquired from MCUXpresso   Elftosb tool – Bootable image generation Then we must generate the boot_image.sb Then call the elftosb tool again with a kinetis command. This will take the .bin file and convert it to a boot_image.sb file. The command is:   elftosb.exe -f kinetis -V -c ../../bd_file/imx10xx/program_flexspinor_image_hyperflash.bd -o boot_image.sb evkbimxrt1050_led_blinky_nopadding.bin   The output of the first imx command we made must match the input of this one. Also, the output must remain named boot_image.sb, otherwise it will not work. Also note that this says flexspinor image hyperflash, but that is correct since we are still technically needing to boot from Hyperflash initially before we copy everything over to SDRAM. Copy the boot_image.sb file. MFG tool Then we can use the mfg tool to generate the program image for the board, and upload it. In order to do this, the board SW7 must be set to OFF-ON-OFF-ON, and switch the jumper from J1  (5-6) to J1 (3-4). Connect the USB cable to J9 to power the board. Then connect the board to your computer and run the Mfg tool. Click start and the image will be uploaded.        Copy the boot_image.sb file that we created in the last step. Move it to the directory Tools > mfgtools-rel > Profiles > MXRT105X > OS Firmware, and drop it in here. Next, set SW7 on the board to OFF-ON-OFF-ON, and switch the jumper at the bottom to power the board. Then connect the USB cable to J9. This will allow you to program the board. Go back to the folder mfgtools-rel and Open the Mfg Tool. It should say HID- compliant vendor-defined device. Otherwise double check SW7 and the power pin at the bottom right.   Click start and if successful it should look like: Please note that this success only means that it was able to upload the bootable image to the board. This usually works well. However, if you find later that the board doesn’t do what it’s supposed to, then there might be a problem in the other steps of the processor. Check to make sure you used the right linker file, and that the settings in MCUXpresso are configured correctly. Press stop and exit Remember to switch the pin headers back, so the board can boot normally. J1 (5-6) and SW7 to OFF-ON -ON -OFF to boot from Hyperflash.   Bootable Image Generation – SRAM This one was a little trickier as there was no appnote, but not too bad. MCUXpresso Configurations and output: Begin by changing memory allocation in the memory configuration editor of the MCU Settings part of MCUXpresso. It should look like the one below. We are linking to copy everything to dtc RAM Then go to settings > MCU C compiler > preprocessor and set the XIP_boot_header enable and and XIP_boot_header_DCD_enable both to 0 Hit apply and close. Go to C/C++ Build >> Settings >> MCU Linker >> Manage linker script, and check the box Link application to RAM.   Go to the debug portion and click on binary utilities, then generate an s-record (.s19) file from MCUXpresso.  Click build to re-build the project. You can verify that application is linked to SRAM in the console: Copy this .s19 file. Elftosb tool – .bin file generation In the flashloader tool, go to Tools > elftosb > Win, and drop the .s19 file in this folder, as well as the dcd.bin file Fire up command prompt in administrator mode, and use command cd [elftosb directory] to get to this folder This step is specific to dtcm ram: Go to Tools >>bd_file >> imx10xx, and open up the imx-dtcm-unsigned-dcd.bd file and change the ivtOffset address to 0x1000. 0x400 is the default for SDCARD booting. To be clear, the bd file should look as below: To generate the .bin file, call the command:   elftosb.exe -f imx -V -c ../../bd_file/imx10xx/imx-dtcm-unsigned-dcd.bd -o evkbimxrt1050_led_blinky.bin SRAM1_led_blinky.s19   This command essentially uses the imx-flexspinor bd linker file to generate a .bin file that will include the dcd.bin header inside. Note that SRAM_led_blinky.s19 should be renamed to your actual file name acquired from MCUXpresso. Elftosb tool – Bootable image generation Then we must generate the boot_image.sb Then call the elftosb tool again with a kinetis command. This will take the .bin file and convert it to a boot_image.sb file. The command is:   elftosb.exe -f kinetis -V -c ../../bd_file/imx10xx/program_flexspinor_image_hyperflash.bd -o boot_image.sb evkbimxrt1050_led_blinky_nopadding.bin   The output of the first imx command we made must match the input of this one. Also, the output must remain named boot_image.sb, otherwise it will not work. Also note that this says flexspinor image hyperflash, but that is correct since we are still technically needing to boot from Hyperflash initially before we copy everything over to SDRAM. MFG tool Then we can use the mfg tool to generate the program image for the board, and upload it. In order to do this, the board SW7 must be set to OFF-ON-OFF-ON, and switch the jumper from J1  (5-6) to J1 (3-4). Connect the USB cable to J9 to power the board. Then connect the board to your computer and run the Mfg tool. Click start and the image will be uploaded.    Copy the boot_image.sb file that we created in the last step. Move it to the directory Tools > mfgtools-rel > Profiles > MXRT105X > OS Firmware, and drop it in here. Next, set SW7 on the board to OFF-ON-OFF-ON, and switch the jumper at the bottom to power the board. Then connect the USB cable to J9. This will allow you to program the board. Go back to the folder mfgtools-rel and Open the Mfg Tool. It should say HID- compliant vendor-defined device. Otherwise double check SW7 and the power pin at the bottom right.   Click start and if successful it should look like: Please note that this success only means that it was able to upload the bootable image to the board. This usually works well. However, if you find later that the board doesn’t do what it’s supposed to, then there might be a problem in the other steps of the processor. Check to make sure you used the right linker file, and that the settings in MCUXpresso are configured correctly. Press stop and exit Remember to switch the pin headers back, so the board can boot normally. J1 (5-6) and SW7 to OFF-ON -ON -OFF to boot from Hyperflash. Please note that this success only means that it was able to upload the bootable image to the board. This usually works well. However, if you find later that the board doesn’t do what it’s supposed to, then there might be a problem with the other steps of the processor. Check to make sure you used the right linker file, and that the settings in MCUXpresso are configured correctly. After this the bootable image will be uploaded to the board and you’ll be good to go!
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The iMX RT1050 ROM will allow you to copy an application image from a serial NOR flash memory on the FlexSPI controller to SDRAM at boot time. If you want to run your application from SDRAM, then when debugging and developing your application you should use an initialization script for the debugger to setup the SDRAM so the application can be downloaded directly to the SDRAM for debugging. When you are ready to have your application boot without the debugger, then you'll need to use the RT flashloader tools to program the application to the flash and configure it to copy to the SDRAM. The attached document contains instructions on how to program a boot image to serial NOR flash (in this case the hyperflash that is on the EVK) that will be copied to the SDRAM at boot time.
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The MIMXRT1050-EVK includes a CMSIS-DAP/DAP-Link interface that includes MSD drag and drop functionality for the HyperFlash on the board. The drag and drop programming functionality can be used to program applications compiled to execute-in-place (XIP) from the HyperFlash memory. In the early SDK versions for RT1050, the projects did not include the flash configuration block and IVT required to make a bootable image across all toolchains. Starting with the SDK 2.3.1 release, projects include XIP files that add this information to the project. This allows for programming a bootable application to the external flash memory directly from the debugger, so many customers might not even need to use the drag-and-drop programming feature any more. Because of the SDK changes, the DAP-Link application has also had changes: Early versions of the DAPLink firmware were setup to work with a raw application binary like those generated by the SDK 2.3.0 for toolchains other than the MCUXpresso IDE. These versions will take the raw application binary and prepend the flash configuration block for the HyperFlash/QSPI and an IVT to make a bootable image. Newer version of the DAPLink firmware are setup to work with a complete bootable binary like those generated by SDK 2.3.1 and later. These versions will not attempt to prepend a flash configuration block and IVT to the application, because these are assumed to already be present. The following table describes the versions of the DAPLink application that have been released. NOTE: the firmware can be updated on the board, so the version on a given board might not match what was originally programmed at manufacture time. The latest version of firmware can be downloaded from www.nxp.com/opensda Board Rev DAPLink MCU GIT SHA from details.txt file NOTE EVK_A2 MK20 34182e2cce4ca99073443ef29fbcfaab9e18caec DAPLink will add FCB and IVT EVK_A3-EVK-A5 MK20 853df431d81359e822f49363891f877f17d31efb DAPLink will add FCB and IVT EVKB_A MK20 853df431d81359e822f49363891f877f17d31efb DAPLink will add FCB and IVT EVKB_A1 MK20 853df431d81359e822f49363891f877f17d31efb DAPLink will add FCB and IVT EVKB_A1 MK20 b3435dbed0ba4f09680e49d2fcfdaab32c7a4c71 DAPLink will NOT add FCB and IVT To use the drag and drop programming: 1. Configure the board for serial downloader mode by setting SW7 to OFF-ON-OFF-ON.  2. Press SW3 to reset the processor. 3. Drag the application binary to the RT1050-EVK drive.  4. Put the board back in internal boot mode by setting SW7 to OFF-ON-ON-OFF. 5. Press SW3 to reset the processor and your application should boot.  There are some limitations to the drag and drop programming to keep in mind: - Only works for Hyperflash/QSPI XIP applications. Doesn't support copying the code from HyperFlash to another memory (like ITCM) for execution - Application initial stack pointer must be located in DTCM - Doesn't support DCD files The flashloader and ROM tools offer a second external memory programming method where the limitations above do not apply: https://www.nxp.com/downloads/en/initialization-boot-device-driver-code-generation/Flashloader_i.MXRT1050_1.0_GA.zip  Refer to AN12107 for more information: https://www.nxp.com/docs/en/application-note/AN12107.pdf?fsrch=1&sr=2&pageNum=1 
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Introduction i.MX RT ROM bootloader provides a wealth of options to enable user programs to start in various ways. In some cases, people want to copy application image from Flash or other storage device to SDRAM and run there. In this article, I record three ways to realize this. Section 2 and 3 shows load image from NOR flash. Section 4 shows load image from SD card. Software and Tools: MCUXpresso IDE v11.1 NXP-MCUBootUtility 2.2.0   MIMXRT1060-EVK   RT1060 SDK v2.7.0   Win10   Add DCD by MCUxpresso IDE If customers use MCUXpresso to develop the project, they can add DCD head by MCUXpresso. To show the work flow, we take evkmimxrt1020_iled_blinky as the example. Step 1: Add the following to Compiler options: XIP_BOOT_HEADER_DCD_ENABLE=1 SKIP_SYSCLK_INIT Step 2: Modify the Memory Configuration Step 3: Select link application to RAM Step 4. Compile the project. MCUXpresso will generate linker script automatically. Step 5. Since the code should be linked to RAM, MCUXpresso will not prefix IVT and DCD. We can add these link information to linker script manually. Add below code to .ld file’s head.     .boot_hdr : ALIGN(4)     {         FILL(0xff)         __boot_hdr_start__ = ABSOLUTE(.) ;         KEEP(*(.boot_hdr.conf))         . = 0x1000 ;         KEEP(*(.boot_hdr.ivt))         . = 0x1020 ;         KEEP(*(.boot_hdr.boot_data))         . = 0x1030 ;         KEEP(*(.boot_hdr.dcd_data))         __boot_hdr_end__ = ABSOLUTE(.) ;         . = 0x2000 ;     } >BOARD_SDRAM   Then deselect “Manage linker script” in last screenshot. Step 6. Recompile the project, IVT/DCD/BOOT_DATA will be add to your project. Then right click the project axf file->Binary Utilities->Create S-record.   After all these step, you can open MCUBootUtility and download the .s19 file to NOR flash.   Add DCD by MCUBootUtility We can also keep the linker script managed by IDE. MCUBootUtility can add head too. Sometimes it is more flexible than other manners. Step 1. This time BOARD_SDRAM location should be changed to 0x80002000 while the size should be 0x1cff000. This is because the start 8k space in bootable image is saved for IVT and DCD. Step 2. compile the project and generate the .s19 file. Step 3. Open MCUBootUtility. In MCUBootUtility, we should first set the Device Configuration Data. Here I use MIMXRT1060_EVK. So I select the DCD bin file in NXP-MCUBootUtility-2.2.0\src\targets\MIMXRT1062. After that, select the application image file and click All-in-one Action button. MCUBootUtility can do all the work without any manual operation.   Boot from SD card to SDRAM In some application, customer don’t want XIP. They want to use SD card to keep application image and run the code in RAM. But if the code size is bigger than OCRAM size, they have to copy image into SDRAM when startup. With MCUBootUtility’s help, this work is very easy too.  User just need to change the memory map which is located to 0x80001000.   In MCUBootUtility, select the Boot Device to “uSDHC SD” and insert SD card. Then connect the target board. If RT1060 can read the SD card, it will display the SD card information. Then same as last section, set the DCD file and application image file. Click the All-in-One Action button, MCUBootUtility will generate the bootable image and write it to SD card.   SD card has huge capacity. It's too wasteful to only store boot image. People may ask that can they also create a FAT32 system and store more data file in it? Yes, but you need tool's help. When booting from SD card, ROM code read IVT and DCD from SD card address 0x400. To FAT32, the first 512 bytes in SD is for MBR(MAIN BOOT RECORD). Data in address 0x1c6 in MBR reords the partition start address. If the space from MBR to partition start address is big enough to store boot image, then FAT32 system and boot image can live in peace. .   Conclusions:      To help Boot ROM initialize SDRAM, DCD must be placed at right place and indexed by IVT correctly. When our code seems not work, we should first check IVT and DCD.          The IVT offset from the base address for each boot device type is defined in the table below. The location of the IVT is the only fixed requirement by the ROM. The remainder or the image memory map is flexible and is determined by the contents of the IVT.
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Introduction  This document is an extension of section 3.1.3, “Software implementation” from the application note AN12077, using the i.MX RT FlexRAM. It's important that before continue reading this document, you read this application note carefully.  Link to the application note.  Section 3.1.3 of the application note explains how to reallocate the FlexRAM through software within the startup code of your application. This document will go into further detail on all the implications of making these modifications and what is the best way to do it.  Prerequisites RT10xx-EVK  The latest SDK which you can download from the following link: Welcome | MCUXpresso SDK Builder MCUXpresso IDE Internal SRAM  The amount of internal SRAM varies depending on the RT. In some cases, not all the internal SRAM can be reallocated with the FlexRAM.  RT  Internal SRAM FlexRAM RT1010 Up to 128 KB Up to 128 KB RT1015 Up to 128 KB Up to 128 KB RT1020 Up to 256 KB Up to 256 KB RT1050 Up to 512 KB Up to 512 KB RT1060 Up to 1MB  Up to 512 KB RT1064 Up to 1MB Up to 512 KB   In the case of the RT106x, only 512 KB out of the 1MB of internal SRAM can be reallocated through the FlexRAM as DTCM, ITCM, and OCRAM. The remaining 512 KB are from OCRAM and cannot be reallocated. For all the other RT10xx you can reallocate the whole internal SRAM either as DTCM, ITCM, and OCRAM. Section 3.1.3.1 of the application note explains the limitations of the size when reallocating the FlexRAM. One thing that's important to mention is that the ROM bootloader in all the RT10xx parts uses the OCRAM, hence you should keep some  OCRAM when reallocating the FlexRAM, this doesn't apply to the RT106x since you will always have the 512 KB of OCRAM that cannot be reallocated. To know more about how many OCRAM each RT family needs please refer to section 2.1.1.1 of the application note. Implementation in MCUXpresso IDE First, you need to import any of the SDK examples into your MCUXpresso IDE workspace. In my case, I imported the igpio_led_output example for the RT1050-EVKB. If you compile this project, you will see that the default configuration for the FlexRAM on the RT1050-EVKB is the following:  SRAM_DTC 128 KB SRAM_ITC 128 KB SRAM_OC 256 KB   Now we need to go to the Reset handler located in the file startup_mimxrt1052.c. Reallocating the FlexRAM has to be done before the FlexRAM is configured, this is why it's done inside the Reset Handler.  The registers that we need to modify to reallocate the FlexRAM are IOMUXC_GPR_GPR16, and IOMUXC_GPR_GPR17. So first we need to have in hand the addresses of these three registers. Register Address IOMUXC_GPR_GPR16 0x400AC040 IOMUXC_GPR_GPR17 0x400AC044   Now, we need to determine how we want to reallocate the FlexRAM to see the value that we need to load into register IOMUXC_GPR_GPR17. In my case, I want to have the following configuration:  SRAM_DTC 256 KB SRAM_ITC 128 KB SRAM_OC 128 KB   When choosing the new sizes of the FlexRAM be sure that you choose a configuration that you can also apply through the FlexRAM fuses, I will explain the reason for this later. The configurations that you can achieve through the fuses are shown in the Fusemap chapter of the reference manual in the table named "Fusemap Descriptions", the fuse name is "Default_FlexRAM_Part".  Based on the following explanation of the IOMUXC_GPR_GPR17 register: The value that I need to load to the register is 0xAAAAFF55. Where the first  4 banks correspond to the 128KB of SRAM_OC, the next 4 banks correspond to the 128KB of SRAM_ITC and the last 8 banks are the 256KB of SRAM_DTC.  Now, that we have all the addresses and the values that we need we can start writing the code in the Reset handler. The first thing to do is load the new value into the register IOMUXC_GPR_GPR17. After, we need to configure register IOMUXC_GPR_GPR16 to specify that the FlexRAM bank configuration should be taken from register IOMUXC_GPR_GPR17 instead of the fuses. Then if in your new configuration of the FlexRAM either the SRAM_DTC or SRAM_ITC are of size 0, you need to disable these memories in the register IOMUXC_GPR_GPR16. At the end your code should look like the following:    void ResetISR(void) { // Disable interrupts __asm volatile ("cpsid i"); /* Reallocating the FlexRAM */ __asm (".syntax unified\n" "LDR R0, =0x400ac044\n"//Address of register IOMUXC_GPR_GPR17 "LDR R1, =0xaaaaff55\n"//FlexRAM configuration DTC = 265KB, ITC = 128KB, OC = 128KB "STR R1,[R0]\n" "LDR R0,=0x400ac040\n"//Address of register IOMUXC_GPR_GPR16 "LDR R1,[R0]\n" "ORR R1,R1,#4\n"//The 4 corresponds to setting the FLEXRAM_BANK_CFG_SEL bit in register IOMUXC_GPR_GPR16 "STR R1,[R0]\n" #ifdef FLEXRAM_ITCM_ZERO_SIZE "LDR R0,=0x400ac040\n"//Address of register IOMUXC_GPR_GPR16 "LDR R1,[R0]\n" "AND R1,R1,#0xfffffffe\n"//Disabling SRAM_ITC in register IOMUXC_GPR_GPR16 "STR R1,[R0]\n" #endif #ifdef FLEXRAM_DTCM_ZERO_SIZE "LDR R0,=0x400ac040\n"//Address of register IOMUXC_GPR_GPR16 "LDR R1,[R0]\n" "AND R1,R1,#0xfffffffd\n"//Disabling SRAM_DTC in register IOMUXC_GPR_GPR16 "STR R1,[R0]\n" #endif ".syntax divided\n"); #if defined (__USE_CMSIS) // If __USE_CMSIS defined, then call CMSIS SystemInit code SystemInit(); ...‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍   If you compile your project you will see the memory distribution that appears on the console is still the default configuration.  This is because we did modify the Reset handler to reallocate the FlexRAM but we haven't modified the linker file to match these new sizes. To do this you need to go to the properties of your project. Once in the properties, you need to go to C/C++ Build -> MCU settings. Once you are in the MCU settings you need to modify the sizes of the SRAM memories to match the new configuration.  When you make these changes click Apply and Close. After making these changes if you compile the project you will see the memory distribution that appears in the console is now matching the new sizes.  Now we need to modify the Memory Protection Unit (MPU) to match these new sizes of the memories. To do this you need to go to the function BOARD_ConfigMPU inside the file board.c. Inside this function, you need to locate regions 5, 6, and 7 which correspond to SRAM_ITC, SRAM_DTC, and SRAM_OC respectively. Same as for register IOMUXC_GPR_GPR14, if the new size of your memory is not 32, 64, 128, 256, or 512 you need to choose the next greater number. Your configuration should look like the following:    /* Region 5 setting: Memory with Normal type, not shareable, outer/inner write back */ MPU->RBAR = ARM_MPU_RBAR(5, 0x00000000U); MPU->RASR = ARM_MPU_RASR(0, ARM_MPU_AP_FULL, 0, 0, 1, 1, 0, ARM_MPU_REGION_SIZE_128KB); /* Region 6 setting: Memory with Normal type, not shareable, outer/inner write back */ MPU->RBAR = ARM_MPU_RBAR(6, 0x20000000U); MPU->RASR = ARM_MPU_RASR(0, ARM_MPU_AP_FULL, 0, 0, 1, 1, 0, ARM_MPU_REGION_SIZE_256KB); /* Region 7 setting: Memory with Normal type, not shareable, outer/inner write back */ MPU->RBAR = ARM_MPU_RBAR(7, 0x20200000U); MPU->RASR = ARM_MPU_RASR(0, ARM_MPU_AP_FULL, 0, 0, 1, 1, 0, ARM_MPU_REGION_SIZE_128KB);‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍   We need to change the image entry address to the Reset handler. To do this, you need to go to the file fsl_flexspi_nor_boot.c inside the xip folder. You need to declare the ResetISR and change the entry address in the image vector table.  Finally, we need to place the stack at the start of the DTCM memory. To do this, we need to go to the properties of your project. From there, we have to C/C++ Build and Manage Linker Script.  From there, we will need to add two more assembly instructions in our ResetISR function. We have to add these two instructions at the beginning of our assembly code:  In the attached c file, you'll find all the assembly instructions mentioned above.  That's it, these are all the changes that you need to make to reallocate the FlexRAM during the startup.  Debug Session  To verify that all the modifications that we just did were correct we will launch the debug session. As soon as we reach the main, before running the application, we will go to the peripheral view to see registers IOMUXC_GPR_GPR16, and IOMUXC_GPR_GPR17 and verify that the values are the correct ones. In register IOMUXC_GPR_GPR16 as shown in the image below we configure the FLEXRAM_BANK_CFG_SEL as 1 to use the use register IOMUXC_GPR_GPR17 to configure the FlexRAM.  Finally, in register IOMUXC_GPR_GPR17 we can see the value 0xAAAAFF55 that corresponds to the new configuration.  Reallocating the FlexRAM through the Fuses  We just saw how to reallocate the FlexRAM through software by writing some code in the Reset Handler. This procedure works fine, however, it's recommended that you use this approach to test the different sizes that you can configure but once you find the correct configuration for your application we highly recommend that you configure these new sizes through the fuses instead of using the register IOMUXC_GPR_GPR17. There are lots of dangerous areas in reconfiguring the FlexRAM in code. It pretty much all boils down to the fact that any code/data/stack information written to the RAM can end up changing location during the reallocation.  This is the reason why once you find the correct configuration, you should apply it through the fuses. If you use the fuses to configure the FlexRAM, then you don't have the same concerns about moving around code and data, as the fuse settings are applied as a hardware default.  Keep in mind that once you burn the fuses there's no way back! This is why it's important that you first try the configuration through the software method. Once you burn the fuses you won't need to modify the Reset handler, you only need to modify the MPU to change the size of regions as we saw before and the MCU settings of your project to match the new memory sizes that you configured through the fuses.  The fuse in charge of the FlexRAM configuration is Default_FlexRAM_Part, the address of this fuse is 0x6D0[15:13]. You can find more information about this fuse and the different configurations in the Fusemap chapter of the reference manual.  To burn the fuses I recommend using either the blhost or the MCUBootUtility.  Link to download the blhost.  Link to the MCUBootUtility webpage.    I hope you find this document helpful!  Víctor Jiménez 
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This document describes the different source clocks and the main modules that manage which clock source is used to derive the system clocks that exists on the i.MX RT’s devices. It’s important to know the different clock sources available on our devices, modifying the default clock configuration may have different purposes since increasing the processor performance, achieving specific baud rates for serial communications, power saving, or simply getting a known base reference for a clock timer. The hardware used for this document is the following: i.MX RT: EVK-MIMXRT1060 Keep in mind that the described hardware and management clock modules in this document are a general overview of the different platforms and the devices listed above are used as a reference example, some terms and hardware modules functionality may vary between devices of the same platform. For more detailed information about the device hardware modules, please refer to your specific device Reference Manual. RT platforms The Clock Controller Module(CCM) facilitates the clock generation in the RT platforms, many clocking variations are possible and the maximum clock frequency for the i.MX RT1060 device is @600MHz.The following image shows a block diagram of the CCM, the three marked sub-modules are important to understand all the clock path from the clock generation(oscillators or crystals) to the clock management for all the peripherals of the board.    Figure 1. Clock Controller Module(CCM) Block Diagram        CCM Analog Submodule This submodule contains all the oscillators and several PLL’s that provide a clock source to the principal CMM module. For example, the i.MX RT1060 device supports 2 internal oscillators that combined with suitable external quartz crystal and external load capacitors provide an accurate clock source, another 2 internal oscillators are available for low power modes and as a backup when the system detects a loss of clock. These oscillators provide a fixed frequency for the several PLL’s inside this module. Internal Clock Sources with external components  Crystal Oscillator @24MHz Many of the serial IO modules depend on the fixed frequency of 24 MHz. The reference clock that generates this crystal oscillator provides an accurate clock source for all the PLL inputs.  Crystal Oscillator @32KHz Generally, RTC oscillators are either implemented with 32 kHz or 32.768 kHz crystals. This Oscillator should always be active when the chip is powered on. Internal Clock sources RC Oscillator @24MHz A lower-power RC oscillator module is available on-chip as a possible alternative to the 24 MHz crystal oscillator after a successful power-up sequence. The 24 MHz RC oscillator is a self-tuning circuit that will output the programmed frequency value by using the RTC clock as its reference. While the power consumption of this RC oscillator is much lower than the 24MHz crystal oscillator, one limitation of this RC oscillator module is that its clock frequency is not as accurate. Oscillator @32KHz The internal oscillator is automatically multiplexed in the clocking system when the system detects a loss of clock. The internal oscillator will provide clocks to the same on-chip modules as the external 32kHz oscillator. Also is used to be useful for quicker startup times and tampering prevention. Note. An external 32KHz clock source must be used since the internal oscillator is not precise enough for long term timekeeping. PLLs There are 7 PLLs in the i.MXRT1060 platform, some with specific functions, for example, create a reference clock for the ARM Core, USB peripherals, etc. Below these PLLs are listed. PLL1 - ARM PLL (functional frequency @600 MHz) PLL2 - System PLL (functional frequency @528 MHz)* PLL3 - USB1 PLL (functional frequency @480 MHz)* PLL4 - Audio PLL PLL5 - Video PLL PLL6 - ENET PLL PLL7 - USB2 PLL (functional frequency @480 MHz) * Two of these PLLs are each equipped with four Phase Fractional Dividers (PFDs) in order to generate additional frequencies for many clock roots.  Each PLLs configuration and control functions like Bypass, Output Enable/Disable, and Power Down modes are accessible individually through its PFDs and global configuration and status registers found at the CCM internal memory registers.        Clock Control Module(CCM) The Clock Control Module (CCM) generates and controls clocks to the various modules in the design and manages low power modes. This module uses the available clock sources(PLL reference clocks and PFDs) to generate the clock roots. There are two important sub-blocks inside the CCM listed below. Clock Switcher This sub-block provides the registers that control which PLLs and PFDs outputs are selected as the reference clock for the Clock Root Generator.  Clock Root Generator This sub-block provides the registers that control most of the secondary clock source programming, including both the primary clock source selection and the clock dividers. The clock roots are each individual clocks to the core, system buses, and all other SoC peripherals, among those, are serial clocks, baud clocks, and special function blocks. All of these clock references are delivered to the Low Power Clock Gating unit(LPCG).        Low Power Clock Gating unit(LPCG) The LPCG block receives the root clocks from CCM and splits them to clock branches for each peripheral. The clock branches are individually gated clocks. The following image shows a detailed block diagram of the CMM with the previously described submodules and how they link together. Figure 2. Clock Management System Example: Configure The ARM Core Clock (PLL1) to a different frequency. The Clock tools available in MCUXpresso IDE, allows you to understand and configure the clock source for the peripherals in the platform. The following diagram shows the default PLL1 mode configured @600MHz, the yellow path shows all the internal modules involved in the clock configuration.  Figure 3. Default PLL configuration after reset. From the previous image notice that PLL1 is attached from the 24MHz oscillator, then the PLL1 is configured with a pre-scaler of 50 to achieve a frequency @1.2GHz, finally, a frequency divider by 2 let a final frequency @600MHz. 1.1 Modify the PLL1 frequency For example, you can use the Clock tools to configure the PLL pre-scaler to 30, select the PLL1 block and then edit the pre-scaler value, therefore, the final clock frequency is @360MHz, these modifications are shown in the following figure.  Figure 4. PLL1 @720MHz, final frequency @360MHz    1.2 Export clock configuration to the project After you complete the clock configuration, the Clock Tool will update the source code in clock_config.c and clock_config.h, including all the clock functional groups that we created with the tool. This will include the clock source for specific peripherals. In the previous example, we configured the PLL1 (ARM PLL) to a functional frequency @360MHz; this is translated to the following structure in source code: “armPllConfig_BOARD_BootClockRUN” and it’s used by “CLOCK_InitArmPll();” inside the “BOARD_BootClockPLL150MRUN();” function.     Figure 5. PLL1 configuration struct  Figure 6. PLL configuration function Example: The next steps describe how to select a clock source for a specific peripheral. 1.1 Configure clock for specific peripheral For example, using the GPT(General Purpose Timer) the available clock sources are the following: Clock Source Off Peripheral Clock High-Frequency Reference Clock Clock Source from an external pin Low-Frequency Reference Clock Crystal Oscillator Figure 7. General Purpose Timer Clocks Diagram Using the available SDK example project “evkmimxrt1060_gpt_timer” a configuration struct for the peripheral “gptConfig” is called from the main initialization function inside the gpt_timer.c source file, the default configuration function with the configuration struct as a parameter, is shown in the following figure. Figure 8. Function that returns a GPT default configuration parameters The function loads several parameters to the configuration struct(gptConfig), one of the fields is the Clock Source configuration, modifying this field will let us select an appropriate clock source for our application, the following figure shows the default configuration parameters inside the “GPT_GetDefaultConfig();” function.  Figure 9. Configuration struct In the default GPT configuration struct, the Peripheral Clock(kGPT_CLockSource_Periph) is selected, the SDK comes with several macros located at “fsl_gpt.h” header file, that helps to select an appropriate clock source. The next figure shows an enumerated type of data that contains the possible clock sources for the GPT.  Figure 10. Available clock sources of the GPT. For example, to select the Low-Frequency Reference Clock the source code looks like the following figure.  Figure 11. Low-Frequency Reference Clock attached to GPT Notice that all the peripherals come with a specific configuration struct and from that struct fields the default clocking parameters can be modified to fit with our timing requirements. 1.2 Modify the Peripheral Clock frequency from Clock Tools One of the GPT clock sources is the “Peripheral Clock Source” this clock line can be modified from the Clock Tools, the following figure shows the default frequency configuration from Clock Tools view. Figure 12. GPT Clock Root inside CMM In the previous figure, the GPT clock line is @75MHz, notice that this is sourced from the primary peripheral clock line that is @600MHz attached to the ARM core clocks. For example, modify the PERCLK_PODF divider selecting it and changing the divider value to 4, the resulting frequency is @37.5Mhz, the following figure illustrates these changes.  Figure 13. GPT & PIT clock line @37.5MHz 1.3 Export clock configuration to the project After you complete the clock configuration, the Clock Tool will update the source code in clock_config.c and clock_config.h, including all the clock functional groups that we created with the tool. This will include the clock source for specific peripherals. In the previous example, we configured the GPT clock root divider by a dividing factor of 4 to achieve a 37.5MHz frequency; this is translated to the following instruction in source code: “CLOCK_SetDiv(kCLOCK_PerclkDiv,3);” inside the “BOARD_BootClockRUN();” function.                Figure 14. Frequency divider function References i.MX RT1060 Processor Reference Manual Also visit LPC's System Clocks  Kinetis System Clocks
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In the SDK_2.7.0_EVKB-IMXRT1050, it contains some eIQ machine learning demo projects, there's the tensorflow_lite_kws among them. It's a keyword spotting example that is based on Keyword spotting for Microcontrollers and it deploys a deepwise separable convolutional neural network called MobileNet in this demo project. It can classify a one-second audio clip as either silence, an unknown word, "yes", "no", "up", "down", "left", "right", "on", "off", "stop", or "go". Figure 1 shows the components that comprise it. Fig 1 Training Our New Model The model we are using is trained with the TensorFlow script which is designed to demonstrate how to build and train a model for audio recognition using TensorFlow. The script makes it very easy to train an audio recognition model. Among other things, it allows us to do the following: Download a dataset with audio featuring 20 spoken words. Choose which subset of words to train the model on. Specify what type of preprocessing to use on the audio. Choose from several different types of the model architecture. Optimize the model for microcontrollers using quantization. When we run the script, it downloads the dataset, trains a model, and outputs a file representing the trained model. We then use some other tools to convert this file into the correct form for TensorFlow Lite. Training in virtual machine (VM) Preparation Make sure the TensorFlow has been installed, and since the script downloads over 2GB of training data, it'll need a good internet connection and enough free space on the machine. Note that: The training process itself can take several hours, be patient. Training To begin the training process, use the following commands to clone ML-KWS-for-MCU. git clone https://github.com/ARM-software/ML-KWS-for-MCU.git‍‍‍‍‍‍ The training scripts are configured via a bunch of command-line flags that control everything from the model’s architecture to the words it will be trained to classify. The following command runs the script that begins training. You can see that it has a lot of command-line arguments: python ML-KWS-for-MCU/train.py --model_architecture ds_cnn --model_size_info 5 64 10 4 2 2 64 3 3 1 1 64 3 3 1 1 64 3 3 1 1 64 3 3 1 1 \ --wanted_words=zero, one, two, three, four, five, six, seven, eight, nine \ --dct_coefficient_count 10 --window_size_ms 40 \ --window_stride_ms 20 --learning_rate 0.0005,0.0001,0.00002 \ --how_many_training_steps 10000,10000,10000 \ --data_dir=./speech_dataset --summaries_dir ./retrain_logs --train_dir ./speech_commands_train ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ Some of these, like --wanted_words=zero, one, two, three, four, five, six, seven, eight, nine. By default, the selected words are yes, no, up, down, left, right, on, off, stop, go, but we can provide any combination of the following words, all of which appear in our dataset: Common commands: yes, no, up, down, left, right, on, off, stop, go, backward, forward, follow, learn Digits zero through nine: zero, one, two, three, four, five, six, seven, eight, nine Random words: bed, bird, cat, dog, happy, house, Marvin, Sheila, tree, wow Others set up the output of the script, such as --train_dir=/content/speech_commands_train, which defines where the trained model will be saved. Leave the arguments as they are, and run it. The script will start off by downloading the Speech Commands dataset (Figure 2), which consists of over 105,000 WAVE audio files of people saying thirty different words. This data was collected by Google and released under a CC BY license, and you can help improve it by contributing five minutes of your own voice. The archive is over 2GB, so this part may take a while, but you should see progress logs, and once it's been downloaded once you won't need to do this step again. You can find more information about this dataset in this Speech Commands paper. Fig 2 Once the downloading has completed, some more output will appear. There might be some warnings, which you can ignore as long as the command continues running. Later, you'll see logging information that looks like this (Figure 3). Fig 3 This shows that the initialization process is done and the training loop has begun. You'll see that it outputs information for every training step. Here's a break down of what it means: Step shows that we're on the step of the training loop. In this case, there are going to be 30,000 steps in total, so you can look at the step number to get an idea of how close it is to finishing. rate is the learning rate that's controlling the speed of the network's weight updates. Early on this is a comparatively high number (0.0005), but for later training cycles it will be reduced 5x, to 0.0001, then to 0.00002 at last. accuracy is how many classes were correctly predicted on this training step. This value will often fluctuate a lot, but should increase on average as training progresses. The model outputs an array of numbers, one for each label, and each number is the predicted likelihood of the input being that class. The predicted label is picked by choosing the entry with the highest score. The scores are always between zero and one, with higher values representing more confidence in the result. cross-entropy is the result of the loss function that we're using to guide the training process. This is a score that's obtained by comparing the vector of scores from the current training run to the correct labels, and this should trend downwards during training. checkpoint After a hundred steps, you should see a line like this: This is saving out the current trained weights to a checkpoint file (Figure 4). If your training script gets interrupted, you can look for the last saved checkpoint and then restart the script with --start_checkpoint=/tmp/speech_commands_train/best/ds_cnn_xxxx.ckpt-400 as a command line argument to start from that point . Fig 4 Confusion Matrix After four hundred steps, this information will be logged: The first section is a confusion matrix. To understand what it means, you first need to know the labels being used, which in this case are "silence", "unknown", "zero", "one", "two", "three", "four", "five", "six", "seven", "eight", and "nine". Each column represents a set of samples that were predicted to be each label, so the first column represents all the clips that were predicted to be silence, the second all those that were predicted to be unknown words, the third "zero", and so on. Each row represents clips by their correct, ground truth labels. The first row is all the clips that were silence, the second clips that were unknown words, the third "zero", etc. This matrix can be more useful than just a single accuracy score because it gives a good summary of what mistakes the network is making. In this example you can see that all of the entries in the first row are zero (Figure 5), apart from the initial one. Because the first row is all the clips that are actually silence, this means that none of them were mistakenly labeled as words, so we have no false negatives for silence. This shows the network is already getting pretty good at distinguishing silence from words. If we look down the first column though, we see a lot of non-zero values. The column represents all the clips that were predicted to be silence, so positive numbers outside of the first cell are errors. This means that some clips of real spoken words are actually being predicted to be silence, so we do have quite a few false positives. A perfect model would produce a confusion matrix where all of the entries were zero apart from a diagonal line through the center. Spotting deviations from that pattern can help you figure out how the model is most easily confused, and once you've identified the problems you can address them by adding more data or cleaning up categories.                                                            Fig 5                                                             Validation After the confusion matrix, you should see a line like Figure 5 shows. It's good practice to separate your data set into three categories. The largest (in this case roughly 80% of the data) is used for training the network, a smaller set (10% here, known as "validation") is reserved for evaluation of the accuracy during training, and another set (the last 10%, "testing") is used to evaluate the accuracy once after the training is complete. The reason for this split is that there's always a danger that networks will start memorizing their inputs during training. By keeping the validation set separate, you can ensure that the model works with data it's never seen before. The testing set is an additional safeguard to make sure that you haven't just been tweaking your model in a way that happens to work for both the training and validation sets, but not a broader range of inputs. The training script automatically separates the data set into these three categories, and the logging line above shows the accuracy of model when run on the validation set. Ideally, this should stick fairly close to the training accuracy. If the training accuracy increases but the validation doesn't, that's a sign that overfitting is occurring, and your model is only learning things about the training clips, not broader patterns that generalize Training Finished In general, training is the process of iteratively tweaking a model’s weights and biases until it produces useful predictions. The training script writes these weights and biases to checkpoint files (Figure 6). Fig 6 A TensorFlow model consists of two main things: The weights and biases resulting from training A graph of operations that combine the model’s input with these weights and biases to produce the model’s output At this juncture, our model’s operations are defined in the Python scripts, and its trained weights and biases are in the most recent checkpoint file. We need to unite the two into a single model file with a specific format, which we can use to run inference. The process of creating this model file is called freezing—we’re creating a static representation of the graph with the weights frozen into it. To freeze our model, we run a script that is called as follows: python ML-KWS-for-MCU/freeze.py --model_architecture ds_cnn --model_size_info 5 64 10 4 2 2 64 3 3 1 1 64 3 3 1 1 64 3 3 1 1 64 3 3 1 1 \ --wanted_words=zero, one, two, three, four, five, six, seven, eight, nine \ --dct_coefficient_count 10 --window_size_ms 40 \ --window_stride_ms 20 --checkpoint ./speech_commands_train/best/ds_cnn_9490.ckpt-21600 \ --output_file=./ds_cnn.pb‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ To point the script toward the correct graph of operations to freeze, we pass some of the same arguments we used in training. We also pass a path to the final checkpoint file, which is the one whose filename ends with the total number of training steps. The frozen graph will be output to a file named ds_cnn.pb. This file is the fully trained TensorFlow model. It can be loaded by TensorFlow and used to run inference. That’s great, but it’s still in the format used by regular TensorFlow, not TensorFlow Lite. Convert to TensorFlow Lite Conversion is a easy step: we just need to run a single command. Now that we have a frozen graph file to work with, we’ll be using toco, the command-line interface for the TensorFlow Lite converter. toco --graph_def_file=./ds_cnn.pb --output_file=./ds_cnn.tflite \ --input_shapes=1,49,10,1 --input_arrays=Reshape_1 --output_arrays='labels_softmax' \ --inference_type=QUANTIZED_UINT8 --mean_values=227 --std_dev_values=1 \ --change_concat_input_ranges=false \ --default_ranges_min=-6 --default_ranges_max =6‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ In the arguments, we specify the model that we want to convert, the output location for the TensorFlow Lite model file, and some other values that depend on the model architecture. we also provide some arguments (inference_type, mean_values, and std_dev_values) that instruct the converter how to map its low-precision values into real numbers. The converted model will be written to ds_cnn.tflite, this a fully formed TensorFlow Lite model! Create a C array We’ll use the xxd command to convert a TensorFlow Lite model into a C array in the following. xxd -i ./ds_cnn.tflite > ./ds_cnn.h cat ./ds_cnn.h‍‍‍‍‍‍‍‍ The final part of the output is the file’s contents, which are a C array and an integer holding its length, as follows: Fig 7 Next, we’ll integrate this newly trained model with the tensorflow_lite_kws project. Using the Model in tensorflow_lite_kws Project To use the new model, we need to do two things: In source/ds_cnn_s_model.h, replace the original model data with our new model. Update the label names in source/kws.cpp with our new ''zero'', ''one'', ''two'', ''three'', ''four'', ''five'', ''six'', ''seven'', ''eight'' and ''nine'' labels. const std::string labels[] = {"Silence", "Unknown","zero", "one", "two", "three","four", "five", "six", "seven","eight", "nine"};‍‍‍ Before running the model in the EVKB-IMXRT1050 board (Figure 8), please refer to the readme.txt to do the preparation, in further, the file also demonstrates the steps of testing, please follow them. Fig 8 Figure 9 shows the testing I did, I've attached the model file, please give a try by yourself. Fig 9
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RT1050 HAB Encrypted Image Generation and Analysis 1, Introduction      The NXP RT series can support multiple boot modes, it incluses: unsigned image mode, HAB signed image mode, HAB encryption image mode, and BEE encryption  image mode.       In order to understand the specific structure of the HAB encryption app, this article will generate a non-XIP app image, then generate the relevant burning file through the elftosb.exe tool in the flashloader i.MX-RT1050, and use MFGTOOL to enter the serial download mode to download the .sb file.       This article will focus on the download steps of RT1050 HAB encryption related operations, and analyze the structure of the HAB encrypted app image.     2, RT1050 HAB Encypted Operation Procedure At first, we analyze the steps of MFGtool burning, which files are needed, so as to give specific preparation, open the ucl2.xml file in the following path of the flashloader: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\mfgtools-rel\Profiles\MXRT105X\OS Firmware Because we need to use the HAB encrypated boot mode, then we will use MXRT105X-SecureBoot, from the ucl2.xml file, we will find the following related code: Fig 1. MXRT1050-SecureBoot structure As you can see from the above, to implement the secure boot of RT1050, you need to prepare these three files: ivt_flashlloader_signed.bin: it is the signed flashloader binary file enable_hab.sb: it is used to modify the SRK and HABmode in the fuse map boot_image.sb: HAB encrypted app program file       Here is a flow chart of the overall HAB encryption operation step, after checking this figure, then we will follow it step by step.     Fig 2. MXRT1050 HAB encrypted image flow chart     The app image we used in this article is the RAM app, so, at first, we need to prepare one RAM based app image. In this document, we are directly use the prepared  RAM based app image: evkbimxrt1050_led_softwarereset_0xa000.s19, this app code function is: After download the code to the MIMXRT1050-EVKB(qspi flash) board, the on board led D18 will blinky and printf the information, after pressing the WAKEUP button SW8, the code will implement software reset and printf the related information. The unsigned code test print result are as follows:      BOARD RESET start.  Helloworld. WAKEUP key pressed, will do software system reset.  BOARD RESET start.  Helloworld. 2.1 CST tool preparation      Because the contains a lot of steps, then customer can refer to the following document do the related configuration, this document, we won’t give the CST configuration detail steps. Please check these documents: https://www.cnblogs.com/henjay724/p/10219459.html https://community.nxp.com/docs/DOC-340904 Security Application Note AN12079 After the CST tool configuration, please copy the cst.exe, crts filder, key folder from cst folder to the same folder that holds elftosb executable files: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\elftosb\win Please also copy SRK_1_2_3_4_fuse.bin and SRK_1_2_3_4_table.bin to the above folder. 2.2  Sign flashloader    Please refer to application note AN12079 chapter 3.3.1, copy flashloader.elf from folder path: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Flashloader And the imx-flexspinor-normal-signed.bd  from folder path: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\bd_file\imx10xx to the folder: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\elftosb\win Please open commander window under the elftosb folder, then input this commander: elftosb.exe -f imx -V -c imx-flexspinor-flashloader-signed.bd -o ivt_flashloader_signed.bin flashloader.elf Fig 3.  Sign flashloader  This steps will generate the  ivt_flashlaoder_signed.bin, which is needed to put under the MFGtool OS Firmware folder, just used for enter the signed flashloader mode. 2.3 SRK and HAB mode fuse modification files Please refer to AN12079 chapter 4.3, copy the enable_hab.bd file from folder path: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\bd_file\imx10xx to this folder path: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\elftosb\win Please refer to the chapter 2.1 generated SRK_1_2_3_4_fuse.bin, modify the enable_hab.bd like the following picture: Fig 4. enable_hab.bd SRK and HAB mode fuse modification Then,  in the elftosb window, please input the following command, just used to generate the enable_hab.sb program file: elftosb.exe -f kinetis -V -c enable_hab.bd -o enable_hab.sb Fig 5. SRK and HAB mode program files generation 2.4 APP Encrypted Image      If you want to do the HAB encrypted image download, you need to prepare one non-XIP app image, here we prepared one RAM based APP srec files.      Because the app file is the RAM files, then we also need the related RAM encrypted .bd files, please copy imx-itcm-encrypted.bd from the folder path:      Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\bd_file\imx10xx to this folder path: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\elftosb\win Open imx-itcm-encrypted.bd, then modify the following content: options {     flags = 0x0c;     # Note: This is an example address, it can be any non-zero address in ITCM region     startAddress = 0x8000;     ivtOffset = 0x1000;     initialLoadSize = 0x2000;     # Note: This is required if the cst and elftsb are not in the same folder     # Note: This is required if the default entrypoint is not the Reset_Handler     #       Please set the entryPointAddress to Reset_Handler address   entryPointAddress = 0x0000a2dd; } Here, we need to note these two points: (1)    ivtOffset = 0x1000; If the external flash is flexspi flash, then we need to modify ivtOffset as 0X1000, if it is the nandflash, we need to use the 0X400. (2) entryPointAddress = 0x0000a2dd; The entryPointsAddress should be the app code reset handlder, it is the app start address+4 data, the entry address is also OK, but we suggest you to use the app Reset_Handler address. Fig 6. App reset handler address Then input the following commander in the elftosb windows: elftosb.exe -f imx -V -c imx-itcm-encrypted.bd -o ivt_evkbimxrt1050_led_softwarereset_0xa000_encrypted.bin evkbimxrt1050_led_softwarereset_0xa000.s19 Fig 7. App HAB Encrypted file generation Please note, we need to record the generated key blob offset address, it is 0XA00, just like the above data in the red frame, this address will be used in the next chapter’s .bd file. After this step, it will generate 7 files:          (1)  ivt_evkbimxrt1050_led_softwarereset_0xa000_encrypted.bin, this file includes the FDCB which is filled with 0, IVT, BD, DCD, APP HAB encrypted image data, CSF data (2)  ivt_evkbimxrt1050_led_softwarereset_0xa000_encrypted_nopadding.bin, compare with ivt_evkbimxrt1050_led_softwarereset_0xa000_encrypted.bin, this file deletes the 0s which is above IVT range. (3)  Csf.bin, it is the HAB data area, you can find the data contains the csf data, it is from 0X8000 to 0X8F80 in the generated ivt_evkbimxrt1050_led_softwarereset_0xa000_encrypted.bin. Fig 8. Csf data and the encrypted app relationship      (4) dek.bin Fig 9. Dek data DEK data is the AES-128 bits key, it is not defined by the customer, it is random generated automatically by the HAB encrypted tool. (5) input.csf Open it, you can find the following content: Fig10. Input csf file content (6) rawbytes.bin,  this is the app image plaintext data, it doesn’t contains the FDCB,IVT,BOOTDATA, DCD, csf etc.    (7) temp.bin, it is the temperate file, compare with ivt_evkbimxrt1050_led_softwarereset_0xa000_encrypted.bin, no csf files.   2.5 HAB Encrypted QSPI program file    Here we need to prepare one program_flexspinor_image_qspinor_keyblob.bd file, and put it under the same folder as elftosb, this file is used to generate the HAB encrypted program .sb file. Because the flashloader package didn’t contains it, then we paste all the related content, and I will also attach it in the attachment. # The source block assign file name to identifiers sources { myBinFile = extern (0); dekFile = extern (1); } constants { kAbsAddr_Start= 0x60000000; kAbsAddr_Ivt = 0x60001000; kAbsAddr_App = 0x60002000; } # The section block specifies the sequence of boot commands to be written to the SB file section (0) { #1. Prepare Flash option # 0xc0000006 is the tag for Serial NOR parameter selection # bit [31:28] Tag fixed to 0x0C # bit [27:24] Option size fixed to 0 # bit [23:20] Flash type option # 0 - QuadSPI SDR NOR # 1 - QUadSPI DDR NOR # 2 - HyperFLASH 1V8 # 3 - HyperFLASH 3V # 4 - Macronix Octal DDR # 6 - Micron Octal DDR # 8 - Adesto EcoXIP DDR # bit [19:16] Query pads (Pads used for query Flash Parameters) # 0 - 1 # 2 - 4 # 3 - 8 # bit [15:12] CMD pads (Pads used for query Flash Parameters) # 0 - 1 # 2 - 4 # 3 - 8 # bit [11: 08] Quad Mode Entry Setting # 0 - Not Configured, apply to devices: # - With Quad Mode enabled by default or # - Compliant with JESD216A/B or later revision # 1 - Set bit 6 in Status Register 1 # 2 - Set bit 1 in Status Register 2 # 3 - Set bit 7 in Status Register 2 # 4 - Set bit 1 in Status Register 2 by 0x31 command # bit [07: 04] Misc. control field # 3 - Data Order swapped, used for Macronix OctaFLASH devcies only (except MX25UM51345G) # 4 - Second QSPI NOR Pinmux # bit [03: 00] Flash Frequency, device specific load 0xc0000006 > 0x2000; # Configure QSPI NOR FLASH using option a address 0x2000 enable flexspinor 0x2000; #2 Erase flash as needed. erase 0x60000000..0x60020000; #3. Program config block # 0xf000000f is the tag to notify Flashloader to program FlexSPI NOR config block to the start of device load 0xf000000f > 0x3000; # Notify Flashloader to response the option at address 0x3000 enable flexspinor 0x3000; #5. Program image load myBinFile > kAbsAddr_Ivt; #6. Generate KeyBlob and program it to flexspinor # Load DEK to RAM load dekFile > 0x10100; # Construct KeyBlob Option #--------------------------------------------------------------------------- # bit [31:28] tag, fixed to 0x0b # bit [27:24] type, 0 - Update KeyBlob context, 1 Program Keyblob to flexspinor # bit [23:20] keyblob option block size, must equal to 3 if type =0, # reserved if type = 1 # bit [19:08] Reserved # bit [07:04] DEK size, 0-128bit 1-192bit 2-256 bit, only applicable if type=0 # bit [03:00] Firmware Index, only applicable if type = 1 # if type = 0, next words indicate the address that holds dek # the 3rd word #---------------------------------------------------------------------------- # tag = 0x0b, type=0, block size=3, DEK size=128bit load 0xb0300000 > 0x10200; # dek address = 0x10100 load 0x00010100 > 0x10204; # keyblob offset in boot image # Note: this is only an example bd file, the value must be replaced with actual # value in users project load 0x0000a000 > 0x10208; enable flexspinor 0x10200; #7. Program KeyBlob to firmware0 region load 0xb1000000 > 0x10300; enable flexspinor 0x10300; }‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ Please note, in the above chapter, fig 7, we mentioned the keyblob offset address, we need to modify it in the following code:     load 0x0000a000 > 0x10208; Now, combine program_flexspinor_image_qspinor_keyblob.bd, ivt_evkbimxrt1050_led_softwarereset_0xa000_encrypted_nopadding.bin and dek.bin file together, we use the following commander to generate the boot_image.sb: elftosb.exe -f kinetis -V -c program_flexspinor_image_qspinor_keyblob.bd -o boot_image.sb ivt_evkbimxrt1050_led_softwarereset_0xa000_encrypted_nopadding.bin dek.bin Fig 11. App HAB encrypted program file generation Until now, we will find, all the related HAB encrypted files is prepared. 2.6 MFG Tool program HAB Encrypted files to RT1050-EVKB        Before we program it, please copy the following 3 files which is in the elftosb folder: ivt_flashloader_signed.bin enable_hab.sb boot_image.sb to this folder: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\mfgtools-rel\Profiles\MXRT105X\OS Firmware Please modify cfg.ini, the file path is: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\mfgtools-rel Modify the content as: [profiles] chip = MXRT105X [platform] board = [LIST] name = MXRT105X-SecureBoot Choose MXRT105X-SecureBoot program mode. Then open the tool MfgTool2.exe, the board MIMXRT1050-EVKB(need to modify the on board resistor, use the qspi flash) mode should be serial download mode, just modify SW7:1-OFF,2-OFF,3-OFF, 4-ON, connect two usb cable between PC and the board J28 and J9. After the connection, you will find the MfgTool2.exe can detect the HID device: Fig 12. MFG tool program After the program is finished, power off the board, modify the boot mode to internal boot, it is SW7:1-OFF,2-OFF,3-ON, 4-OFF,connect the COM terminal, power on the EVKB board, after reset, you will find the D18 led is blinking, after you press the SW8, you will find the following printf information: BOARD RESET start. Helloworld. WAKEUP key pressed, will do software system reset. ? BOARD RESET start. Helloworld.‍‍‍‍‍‍‍‍‍‍‍‍‍ So, the HAB encrypted image works OK now. 3. App HAB encrypted image structure analysis 3.1 MCUBootUtility Configuration to check the RT Encrypted image      Here, we can also use  MCUBootUtility tool to check the RT chip encrypted image and the fuse data.      If the cst is your own configured, please do the following configuration at first:     (1)Copy the configured cst folder to folder: NXP-MCUBootUtility-2.0.0\tools Delete the original cst folder. (2)Copy SRK_1_2_3_4_fuse.bin and SRK_1_2_3_4_table.bin to folder:  NXP-MCUBootUtility-2.0.0\gen\hab_cert Now, you can use the new MCUBootutility to connect your board which already done the HAB encrypted method. 3.1 RT1050 fuse map comparation Before do the HAB encrypted image program, I have read out the whole fuse map as follows: Fig 13. MIMXRT1050-EVKB fuse map before HAB encrypted image Fig 14. MIMXRT1050-EVKB fuse map after HAB encrypted image Compare the fuse map between do the HAB encrypted image and no HAB encrypted image, we can find two difference: HAB mode, 0X460 bit1:0 open, 1 close SRK area We can find, after program the HAB encrypted image, the SRK fuse data is the same as the SRK data which is defined in the enable_hab.bd. 3.2  Readout HAB encrypted QSPI APP image structure analysis From MCUBootUtility tool, we can find the HAB Encypted image structure should be like this: Fig 15. HAB Encrypted image structure What about the real example image case? Now, we use the MCUbootUtility tool to read out our HAB encrypted image, from address 0X60000000, the readout size is 0XB000. The detail image structure is like following: Fig 16. HAB Encypted image example structure   1): IVT:  hdr,  IVT header, more details, check hab_hdr 2):    IVT: entry, the app entrypointAddress, it should be the reset_handler address, in this document example, it is the address 0xa004 data, the plaintext is 0X00A2DD, but after the HAB encrypted, we can find the address -x60002004 data is the encrypted data 3):  IVT: reserved 4):  IVT: DCD, it is used for the DRAM SEMC configuration, in this example, we didn’t use the SDDRAM, so the data is 0. 5):  IVT: BOOT_DATA, used to indicate the BOOT_DATA  RAM start address 0X9020. 6):  IVT: self, ivt self RAM start address is 0X9000 7):  IVT:CSF, it is used to indicate the CST start address, this example csf ram address is 0X00010000. 8):  IVT:reserved 9): BOOT_DATA:  RAM image start,  the whole image RAM start address, this RAM example BOOT_DATA is 0X8000,0XA000-0X2000=0X8000 10): BOOT_DATA: size, APP while size, it is 0X0000A200, after checking the while generated HAB encrypted app image size, you can find the image end size is really 0XA200, just lke the fig 16. 11):  HAB  Encypted app data,  please check ivt_evkbimxrt1050_led_softwarereset_0xa000_encrypted.bin file, the address 0X2000-0X7250 data, you will find it is the same.   12): HAB data, it incluses the csf, certificate etc data, you can compare the file ivt_evkbimxrt1050_led_softwarereset_0xa000_encrypted.bin address 0X8000-0x8f70 data, it is the same. 13):DEK blob, it is the DEK key blob related data, the offset address is 0XA000, the same as fig 7. FDCB,IVT,BOOT DATA are all plaintext, but app image area is the HAB encrypted data, HAB and the DEK blocb is the generated data put in the related memory. Conclusion     This document we mainly use the elftosb and the MFGTool to generate the HAB encrypted image, and download it to the RT1050 EVKB board, document give the whole detail steps, and us ethe MCUBootutility tool to read out the HAB encrypted image, and analysis the HAB encrypted image structure with the examples.  After compare with the generated mid files, we can find all the data is consist, and all the encrypted data range is the same. The test result also demonstrate the HAB encrypted code function works, the HAB encrypted boot has no problems. All the related files is in the attachment.      
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As we know, the RT series MCUs support the XIP (Execute in place) mode and benefit from saving the number of pins, serial NOR Flash is most commonly used, as the FlexSPI module can high efficient fetch the code and data from the Serial NOR flash for Cortex-M7 to execute. The fetch way is implementing via utilizing the Quad IO Fast Read command, meanwhile, the serail NOR flash works in the SDR (Single Data transfer Rate) mode, it receives data on SCLK rise edge and transmits data on SCLK fall edge. Comparing to the SDR mode, the DDR (Dual Data transfer Rate) mode has a higher throughput capacity, whether it can provide better performance of XIP mode, and how to do that if we want the Serial NOR Flash to work in DDR (Dual Data transfer Rate) mode? SDR & DDR mode SDR mode: In SDR (Single Data transfer Rate) mode, data is only clocked on one edge of the clock (either the rising or falling edge). This means that for SDR to have data being transmitted at X Mbps, the clock bit rate needs to be 2X Mbps. DDR mode: For DDR (Dual Data transfer Rate) mode, also known as DTR (Dual Transfer Rate) mode, data is transferred on both the rising and falling edge of the clock. This means data is transmitted at X Mbps only requires the clock bit rate to be X Mbps, hence doubling the bandwidth (as Fig 1 shows).   Fig 1 Enable DDR mode The below steps illustrate how to make the i.MX RT1060 boot from the QSPI with working in DDR mode. Note: The board is MIMXRT1060, IDE is MCUXpresso IDE Open a hello_world as the template Modify the FDCB(Flash Device Configuration Block) a)Set the controllerMiscOption parameter to supports DDR read command. b) Set Serial Flash frequency to 60 MHz. c)Parase the DDR read command into command sequence. The following table shows a template command sequence of DDR Quad IO FAST READ instruction and it's almost matching with the FRQDTR (Fast Read Quad IO DTR) Sequence of IS25WP064 (as Fig 2 shows).   Fig2 FRQDTR Sequence d)Adjust the dummy cycles. The dummy cycles should match with the specific serial clock frequency and the default dummy cycles of the FRQDTR sequence command is 6 (as the below table shows).   However, when the serial clock frequency is 60MHz, the dummy cycle should change to 4 (as the below table shows).   So it needs to configure [P6:P3] bits of the Read Register (as the below table shows) via adding the SET READ PARAMETERS command sequence(as Fig 3 shows) in FDCB manually. Fig 3 SET READ PARAMETERS command sequence In further, in DDR mode, the SCLK cycle is double the serial root clock cycle. The operand value should be set as 2N, 2N-1 or 2*N+1 depending on how the dummy cycles defined in the device datasheet. In the end, we can get an adjusted FCDB like below. // Set Dummy Cycles #define FLASH_DUMMY_CYCLES 8 // Set Read register command sequence's Index in LUT table #define CMD_LUT_SEQ_IDX_SET_READ_PARAM 7 // Read,Read Status,Write Enable command sequences' Index in LUT table #define CMD_LUT_SEQ_IDX_READ 0 #define CMD_LUT_SEQ_IDX_READSTATUS 1 #define CMD_LUT_SEQ_IDX_WRITEENABLE 3 const flexspi_nor_config_t qspiflash_config = { .memConfig = { .tag = FLEXSPI_CFG_BLK_TAG, .version = FLEXSPI_CFG_BLK_VERSION, .readSampleClksrc=kFlexSPIReadSampleClk_LoopbackFromDqsPad, .csHoldTime = 3u, .csSetupTime = 3u, // Enable DDR mode .controllerMiscOption = kFlexSpiMiscOffset_DdrModeEnable | kFlexSpiMiscOffset_SafeConfigFreqEnable, .sflashPadType = kSerialFlash_4Pads, //.serialClkFreq = kFlexSpiSerialClk_100MHz, .serialClkFreq = kFlexSpiSerialClk_60MHz, .sflashA1Size = 8u * 1024u * 1024u, // Enable Flash register configuration .configCmdEnable = 1u, .configModeType[0] = kDeviceConfigCmdType_Generic, .configCmdSeqs[0] = { .seqNum = 1, .seqId = CMD_LUT_SEQ_IDX_SET_READ_PARAM, .reserved = 0, }, .lookupTable = { // Read LUTs [4*CMD_LUT_SEQ_IDX_READ] = FLEXSPI_LUT_SEQ(CMD_SDR, FLEXSPI_1PAD, 0xED, RADDR_DDR, FLEXSPI_4PAD, 0x18), // The MODE8_DDR subsequence costs 2 cycles that is part of the whole dummy cycles [4*CMD_LUT_SEQ_IDX_READ + 1] = FLEXSPI_LUT_SEQ(MODE8_DDR, FLEXSPI_4PAD, 0x00, DUMMY_DDR, FLEXSPI_4PAD, FLASH_DUMMY_CYCLES-2), [4*CMD_LUT_SEQ_IDX_READ + 2] = FLEXSPI_LUT_SEQ(READ_DDR, FLEXSPI_4PAD, 0x04, STOP, FLEXSPI_1PAD, 0x00), // READ STATUS REGISTER [4*CMD_LUT_SEQ_IDX_READSTATUS] = FLEXSPI_LUT_SEQ(CMD_SDR, FLEXSPI_1PAD, 0x05, READ_SDR, FLEXSPI_1PAD, 0x01), [4*CMD_LUT_SEQ_IDX_READSTATUS + 1] = FLEXSPI_LUT_SEQ(STOP, FLEXSPI_1PAD, 0x00, 0, 0, 0), // WRTIE ENABLE [4*CMD_LUT_SEQ_IDX_WRITEENABLE] = FLEXSPI_LUT_SEQ(CMD_SDR,FLEXSPI_1PAD, 0x06, STOP, FLEXSPI_1PAD, 0x00), // Set Read register [4*CMD_LUT_SEQ_IDX_SET_READ_PARAM] = FLEXSPI_LUT_SEQ(CMD_SDR,FLEXSPI_1PAD, 0x63, WRITE_SDR, FLEXSPI_1PAD, 0x01), [4*CMD_LUT_SEQ_IDX_SET_READ_PARAM + 1] = FLEXSPI_LUT_SEQ(STOP,FLEXSPI_1PAD, 0x00, 0, 0, 0), }, }, .pageSize = 256u, .sectorSize = 4u * 1024u, .blockSize = 64u * 1024u, .isUniformBlockSize = false, }; Is DDR mode real better? According to the RT1060's datasheet, the below table illustrates the maximum frequency of FlexSPI operation, as the MIMXRT1060's onboard QSPI flash is IS25WP064AJBLE, it doesn't contain the MQS pin, it means set MCR0.RXCLKsrc=1 (Internal dummy read strobe and loopbacked from DQS) is the most optimized option. operation mode RXCLKsrc=0 RXCLKsrc=1 RXCLKsrc=3 SDR 60 MHz 133 MHz 166 MHz DDR 30 MHz 66 MHz 166 MHz In another word, QSPI can run up to 133 MHz in SDR mode versus 66 MHz in DDR mode. From the perspective of throughput capacity, they're almost the same. It seems like DDR mode is not a better option for IS25WP064AJBLE and the following experiment will validate the assumption. Experiment mbedtls_benchmark I use the mbedtls_benchmark as the first testing demo and I run the demo under the below conditions: 100MH, SDR mode; 133MHz, SDR mode; 66MHz, DDR mode; According to the corresponding printout information (as below shows), I make a table for comparison and I mark the worst performance of implementation items among the above three conditions, just as Fig 4 shows. SDR Mode run at 100 MHz. FlexSPI clock source is 3, FlexSPI Div is 6, PllPfd2Clk is 720000000 mbedTLS version 2.16.6 fsys=600000000 Using following implementations: SHA: DCP HW accelerated AES: DCP HW accelerated AES GCM: Software implementation DES: Software implementation Asymmetric cryptography: Software implementation MD5 : 18139.63 KB/s, 27.10 cycles/byte SHA-1 : 44495.64 KB/s, 12.52 cycles/byte SHA-256 : 47766.54 KB/s, 11.61 cycles/byte SHA-512 : 2190.11 KB/s, 267.88 cycles/byte 3DES : 1263.01 KB/s, 462.49 cycles/byte DES : 2962.18 KB/s, 196.33 cycles/byte AES-CBC-128 : 52883.94 KB/s, 10.45 cycles/byte AES-GCM-128 : 1755.38 KB/s, 329.33 cycles/byte AES-CCM-128 : 2081.99 KB/s, 279.72 cycles/byte CTR_DRBG (NOPR) : 5897.16 KB/s, 98.15 cycles/byte CTR_DRBG (PR) : 4489.58 KB/s, 129.72 cycles/byte HMAC_DRBG SHA-1 (NOPR) : 1297.53 KB/s, 448.03 cycles/byte HMAC_DRBG SHA-1 (PR) : 1205.51 KB/s, 486.04 cycles/byte HMAC_DRBG SHA-256 (NOPR) : 1786.18 KB/s, 327.70 cycles/byte HMAC_DRBG SHA-256 (PR) : 1779.52 KB/s, 328.93 cycles/byte RSA-1024 : 202.33 public/s RSA-1024 : 7.00 private/s DHE-2048 : 0.40 handshake/s DH-2048 : 0.40 handshake/s ECDSA-secp256r1 : 9.00 sign/s ECDSA-secp256r1 : 4.67 verify/s ECDHE-secp256r1 : 5.00 handshake/s ECDH-secp256r1 : 9.33 handshake/s   DDR Mode run at 66 MHz. FlexSPI clock source is 2, FlexSPI Div is 5, PllPfd2Clk is 396000000 mbedTLS version 2.16.6 fsys=600000000 Using following implementations: SHA: DCP HW accelerated AES: DCP HW accelerated AES GCM: Software implementation DES: Software implementation Asymmetric cryptography: Software implementation MD5 : 16047.13 KB/s, 27.12 cycles/byte SHA-1 : 44504.08 KB/s, 12.54 cycles/byte SHA-256 : 47742.88 KB/s, 11.62 cycles/byte SHA-512 : 2187.57 KB/s, 267.18 cycles/byte 3DES : 1262.66 KB/s, 462.59 cycles/byte DES : 2786.81 KB/s, 196.44 cycles/byte AES-CBC-128 : 52807.92 KB/s, 10.47 cycles/byte AES-GCM-128 : 1311.15 KB/s, 446.53 cycles/byte AES-CCM-128 : 2088.84 KB/s, 281.08 cycles/byte CTR_DRBG (NOPR) : 5966.92 KB/s, 97.55 cycles/byte CTR_DRBG (PR) : 4413.15 KB/s, 130.42 cycles/byte HMAC_DRBG SHA-1 (NOPR) : 1291.64 KB/s, 449.47 cycles/byte HMAC_DRBG SHA-1 (PR) : 1202.41 KB/s, 487.05 cycles/byte HMAC_DRBG SHA-256 (NOPR) : 1748.38 KB/s, 328.16 cycles/byte HMAC_DRBG SHA-256 (PR) : 1691.74 KB/s, 329.78 cycles/byte RSA-1024 : 201.67 public/s RSA-1024 : 7.00 private/s DHE-2048 : 0.40 handshake/s DH-2048 : 0.40 handshake/s ECDSA-secp256r1 : 8.67 sign/s ECDSA-secp256r1 : 4.67 verify/s ECDHE-secp256r1 : 4.67 handshake/s ECDH-secp256r1 : 9.00 handshake/s   Fig 4 Performance comparison We can find that most of the implementation items are achieve the worst performance when QSPI works in DDR mode with 66 MHz. Coremark demo The second demo is running the Coremark demo under the above three conditions and the result is illustrated below. SDR Mode run at 100 MHz. FlexSPI clock source is 3, FlexSPI Div is 6, PLL3 PFD0 is 720000000 2K performance run parameters for coremark. CoreMark Size : 666 Total ticks : 391889200 Total time (secs): 16.328717 Iterations/Sec : 2449.671999 Iterations : 40000 Compiler version : MCUXpresso IDE v11.3.1 Compiler flags : Optimization most (-O3) Memory location : STACK seedcrc : 0xe9f5 [0]crclist : 0xe714 [0]crcmatrix : 0x1fd7 [0]crcstate : 0x8e3a [0]crcfinal : 0x25b5 Correct operation validated. See readme.txt for run and reporting rules. CoreMark 1.0 : 2449.671999 / MCUXpresso IDE v11.3.1 Optimization most (-O3) / STACK   SDR Mode run at 133 MHz. FlexSPI clock source is 3, FlexSPI Div is 4, PLL3 PFD0 is 664615368 2K performance run parameters for coremark. CoreMark Size : 666 Total ticks : 391888682 Total time (secs): 16.328695 Iterations/Sec : 2449.675237 Iterations : 40000 Compiler version : MCUXpresso IDE v11.3.1 Compiler flags : Optimization most (-O3) Memory location : STACK seedcrc : 0xe9f5 [0]crclist : 0xe714 [0]crcmatrix : 0x1fd7 [0]crcstate : 0x8e3a [0]crcfinal : 0x25b5 Correct operation validated. See readme.txt for run and reporting rules. CoreMark 1.0 : 2449.675237 / MCUXpresso IDE v11.3.1 Optimization most (-O3) / STACK   DDR Mode run at 66 MHz. FlexSPI clock source is 2, FlexSPI Div is 5, PLL3 PFD0 is 396000000 2K performance run parameters for coremark. CoreMark Size : 666 Total ticks : 391890772 Total time (secs): 16.328782 Iterations/Sec : 2449.662173 Iterations : 40000 Compiler version : MCUXpresso IDE v11.3.1 Compiler flags : Optimization most (-O3) Memory location : STACK seedcrc : 0xe9f5 [0]crclist : 0xe714 [0]crcmatrix : 0x1fd7 [0]crcstate : 0x8e3a [0]crcfinal : 0x25b5 Correct operation validated. See readme.txt for run and reporting rules. CoreMark 1.0 : 2449.662173 / MCUXpresso IDE v11.3.1 Optimization most (-O3) / STACK   After comparing the CoreMark scores, it gets the lowest CoreMark score when QSPI works in DDR mode with 66 MHz. However, they're actually pretty close. Through the above two testings, we can get the DDR mode maybe not a better option, at least for the i.MX RT10xx series MCU.
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LittleFS is a file system used for microcontroller internal flash and external NOR flash. Since it is more suitable for small embedded systems than traditional FAT file systems, more and more people are using it in their projects. So in addition to NOR/NAND flash type storage devices, can LittleFS be used in SD cards? It seems that it is okay too. This article will use the littlefs_shell and sdcard_fatfs demo project in the i.mxRT1050 SDK to make a new littefs_shell project for reading and writing SD cards. This experiment uses MCUXpresso IDE v11.7, and the SDK uses version 2.13. The littleFS file system has only 4 files, of which the current version shown in lfs.h is littleFS 2.5. The first step, of course, is to add SD-related code to the littlefs_shell project. The easiest way is to import another sdcard_fatfs project and copy all of the sdmmc directories into our project. Then copy sdmmc_config.c and sdmmc_config.h in the /board directory, and fsl_usdhc.c and fsl_usdhc.h in the /drivers directory. The second step is to modify the program to include SD card detection and initialization, adding a bridge from LittleFS to SD drivers. Add the following code to littlefs_shell.c. extern sd_card_t m_sdCard; status_t sdcardWaitCardInsert(void) { BOARD_SD_Config(&m_sdCard, NULL, BOARD_SDMMC_SD_HOST_IRQ_PRIORITY, NULL); /* SD host init function */ if (SD_HostInit(&m_sdCard) != kStatus_Success) { PRINTF("\r\nSD host init fail\r\n"); return kStatus_Fail; } /* wait card insert */ if (SD_PollingCardInsert(&m_sdCard, kSD_Inserted) == kStatus_Success) { PRINTF("\r\nCard inserted.\r\n"); /* power off card */ SD_SetCardPower(&m_sdCard, false); /* power on the card */ SD_SetCardPower(&m_sdCard, true); // SdMmc_Init(); } else { PRINTF("\r\nCard detect fail.\r\n"); return kStatus_Fail; } return kStatus_Success; } status_t sd_disk_initialize() { static bool isCardInitialized = false; /* demostrate the normal flow of card re-initialization. If re-initialization is not neccessary, return RES_OK directly will be fine */ if(isCardInitialized) { SD_Deinit(&m_sdCard); } if (kStatus_Success != SD_Init(&m_sdCard)) { SD_Deinit(&m_sdCard); memset(&m_sdCard, 0U, sizeof(m_sdCard)); return kStatus_Fail; } isCardInitialized = true; return kStatus_Success; } In main(), add these code if (sdcardWaitCardInsert() != kStatus_Success) { return -1; } status = sd_disk_initialize(); Next, create two new c files, lfs_sdmmc.c and lfs_sdmmc_bridge.c. The call order is littlefs->lfs_sdmmc.c->lfs_sdmmc_bridge.c->fsl_sd.c. lfs_sdmmc.c and lfs_sdmmc_bridge.c acting as intermediate layers that can connect the LITTLEFS and SD upper layer drivers. One of the things that must be noted is the mapping of addresses. The address given by littleFS is the block address + offset address. See figure below. This is a read command issued by the ‘mount’ command. The block address refers to the address of the erased sector address in SD. The read and write operation uses the smallest read-write block address (BLOCK) of SD, as described below. Therefore, in lfs_sdmmc.c, the address given by littleFS is first converted to the byte address. Then change the SD card read-write address to the BLOCK address in lfs_sdmmc_bridge.c. Since most SD cards today exceed 4GB, the byte address requires a 64-bit variable. Finally, the most important step is littleFS parameter configuration. There is a structure LittlsFS_config in peripherals.c, which contains not only the operation functions of the SD card, but also the read and write sectors and cache size. The setup of this structure is critical. If the setting is not good, it will not only affect the performance, but also cause errors in operation. Before setting it up, let's introduce some of the general ideal of SD card and littleFS. The storage unit of the SD card is BLOCK, and both reading and writing can be carried out according to BLOCK. The size of each block can be different for different cards. For standard SD cards, the length of the block command can be set with CMD16, and the block command length is fixed at 512 bytes for SDHC cards. The SD card is erased sector by sector. The size of each sector needs to be checked in the CSD register of the SD card. If the CSD register ERASE_BLK_EN = 0, Sector is the smallest erase unit, and its unit is "block". The value of sector size is equal to the value of the SECTOR_SIZE field in the CSD register plus 1. For example, if SECTOR_SIZE is 127, then the minimum erase unit is 512*(127+1)=65536 bytes. In addition, sometimes there are doubts, many of the current SD cards actually have wear functions to reduce the loss caused by frequent erasing and writing, and extend the service life. So in fact, delete operations or read and write operations are not necessarily real physical addresses. Instead, it is mapped by the SD controller. But for the user, this mapping is transparent. So don't worry about this affecting normal operation. LittleFS is a lightweight file system that has power loss recovery and dynamic wear leveling compared to FAT systems. Once mounted, littleFS provides a complete set of POSIX-like file and directory functions, so it can be operated like a common file system. LittleFS has only 4 files in total, and it basically does not need to be modified when used. Since the NOR/NAND flash to be operated by LittleFS is essentially a block device, in order to facilitate use, LittleFS is read and written in blocks, and the underlying NOR/NAND Flash interface drivers are carried out in blocks. Let's take a look at the specific content of LittleFS configuration parameters. const struct lfs_config LittleFS_config = { .context = (void*)0, .read = lfs_sdmmc_read, .prog = lfs_sdmmc_prog, .erase = lfs_sdmmc_erase, .sync = lfs_sdmmc_sync, .read_size = 512, .prog_size = 512, .block_size = 65536, .block_count = 128, .block_cycles = 100, .cache_size = 512, .lookahead_size = LITTLEFS_LOOKAHEAD_SIZE }; Among them, the first item (.context) is not used in this project, and is used in the original project to save the offset of the file system stored in Flash. Items two (.read) through five (.sync) point to the handlers for each operation. The sixth item (.read_size) is the smallest unit of read operation. This value is roughly equal to the BLOCK size of the SD card. In the SD card driver, this size has been fixed to 512. So for convenience, it is also set to 512. The seventh item (.prog_size) is the number of bytes written each time, which is 512 bytes like .read_size. The eighth item is .block_size. This can be considered to be the smallest erase block supported by the SD card when performing an erase operation. Here the default value is not important, you need to set it in the program according to the actual value after the SD card is initialized. The card used in this experiment is 64k bytes as an erase block, so 65536 is used directly here. Item 9 (.block_count) is used to indicate how many erasable blocks there are. Multiply the .block_size to get the size of the card. If the card is replaceable, it needs to be determined according to the parameters after the SD card is initialized. The tenth item (.block_cycles) is the number of erase cycles per block. Item 11 (.cache_size) is about the cache buffer. It feels like bigger is better, but actually modifies this value won't work. So still 512. Item 12 (lookahead_size), littleFS uses a lookahead buffer to manage and allocate blocks. A lookahead buffer is a fixed-size bitmap that records information about block allocations within an area. The lookahead buffer only records the information of block allocations in one area, and when you need to know the allocation of other regions, you need to scan the file system to find allocated blocks. If there are no free blocks in the lookahead buffer, you need to move the lookahead buffer to find other free blocks in the file system. The lookahead buffer position shifts one lookahead_size at a time. Use the original value here.  That’s all for the porting work. We can test the project now. You can see it works fine. The littleFS-SD project can read/write/create folder and erase. And it also support append to an exist file. But after more testing, a problem was found, if you repeatedly add->-close->-add-> close a file, the file will open more and more slowly, even taking a few seconds. This is what should be added and is not written directly in the last block of the file, but will apply for a new block, regardless of whether the previous block is full or not. See figure below. The figure above prints out all the read, write, and erase operations used in each write command. You can see that each time in the lfs_file_open there is one more read than the last write operation. In this way, after dozens or hundreds of cycles, a file will involve many blocks. It is very time-consuming to read these blocks in turn. Tests found that more than 100 read took longer than seconds. To speed things up, it is recommended to copy the contents of one file to another file after adding it dozens of times. In this way, the scattered content will be consolidated to write a small number of blocks. This can greatly speed up reading and writing.
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Introduction NXP i.MXRT106x has two USB2.0 OTG instance. And the RT1060 EVK has both of the USB interface on the board. But the RT1060 SDK only has single USB host example. Although RT1060’s USB host stack support multiple devices, but we still need a USB HUB when user want to connect two device. This article will show you how to make both USB instance as host. RT1060 SDK has single host examples which support multiple devices, like host_hid_mouse_keyboard_bm. But this application don’t use these examples. Instead, MCUXpresso Config Tools is used to build the demo from beginning. The config tool is a very powerful tool which can configure clock, pin and peripherals, especially the USB. In this application demo, it can save 95% coding work. Hardware and software tools RT1060 EVK MCUXpresso 11.4.0 MIMXRT1060 SDK 2.9.1 Step 1 This project will support USB HID mouse and USB CDC. First, create an empty project named MIMXRT1062_usb_host_dual_port. When select SDK components, select “USB host CDC” and “”USB host HID” in Middleware label. IDE will select other necessary component automatically.     After creating the empty project, clock should be configured first. Both of the USB PHY need 480M clock.   Step 2 Next step is to configure USB host in peripheral config tool. Due to the limitation of config tool, only one host instance of the USB component is allowed. In this project, CDC VCOM is added first.   Step 3 After these settings, click “Update Code” in control bar. This will turn all the configurations into code and merge into project. Then click the “copy to clipboard” button. This will copy the host task call function. Paste it in the forever while loop in the project’s main(). Besides that, it also need to add BOARD_InitBootPeripherals() function call in main(). At this point, USB VCOM is ready. The tool will not only copy the file and configure USB, but also create basic implementation framework. If compile and download the project to RT1060 EVK, it can enumerate a USB CDC VCOM device on USB1. If characters are send from CDC device, the project can send it out to DAPLink UART port so that you can see the character on a terminal interface in computer. Step 4 To get USB HID mouse code, it need to create another USB HID project. The workflow is similar to the first project. Here is the screenshot of the USB HID configuration.   Click “Update code”, the HID mouse code will be generated. The config tool generate two files, usb_host_interface_0_hid_mouse.c and usb_host_interface_0_hid_mouse. Copy them to the “source” folder in dual host project.     Step 5 Next step is to modify some USB macro definitions. <usb_host_config.h> #define USB_HOST_CONFIG_EHCI 2 /*means there are two host instance*/ #define USB_HOST_CONFIG_MAX_HOST 2 /*The USB driver can support two ehci*/ #define USB_HOST_CONFIG_HID (1U) /*for mouse*/ Next step is merge usb_host_app.c. The project initialize USB hardware and software in USB_HostApplicationInit(). usb_status_t USB_HostApplicationInit(void) { usb_status_t status; USB_HostClockInit(kUSB_ControllerEhci0); USB_HostClockInit(kUSB_ControllerEhci1); #if ((defined FSL_FEATURE_SOC_SYSMPU_COUNT) && (FSL_FEATURE_SOC_SYSMPU_COUNT)) SYSMPU_Enable(SYSMPU, 0); #endif /* FSL_FEATURE_SOC_SYSMPU_COUNT */ status = USB_HostInit(kUSB_ControllerEhci0, &g_HostHandle[0], USB_HostEvent); status = USB_HostInit(kUSB_ControllerEhci1, &g_HostHandle[1], USB_HostEvent); /*each usb instance have a g_HostHandle*/ if (status != kStatus_USB_Success) { return status; } else { USB_HostInterface0CicVcomInit(); USB_HostInterface0HidMouseInit(); } USB_HostIsrEnable(); return status; } In USB_HostIsrEnable(), add code to enable USB2 interrupt.   irqNumber = usbHOSTEhciIrq[1]; NVIC_SetPriority((IRQn_Type)irqNumber, USB_HOST_INTERRUPT_PRIORITY); EnableIRQ((IRQn_Type)irqNumber); Then add and modify USB interrupt handler. void USB_OTG1_IRQHandler(void) { USB_HostEhciIsrFunction(g_HostHandle[0]); } void USB_OTG2_IRQHandler(void) { USB_HostEhciIsrFunction(g_HostHandle[1]); } Since both USB instance share the USB stack, When USB event come, all the event will call USB_HostEvent() in usb_host_app.c. HID code should also be merged into this function. static usb_status_t USB_HostEvent(usb_device_handle deviceHandle, usb_host_configuration_handle configurationHandle, uint32_t eventCode) { usb_status_t status1; usb_status_t status2; usb_status_t status = kStatus_USB_Success; /* Used to prevent from multiple processing of one interface; * e.g. when class/subclass/protocol is the same then one interface on a device is processed only by one interface on host */ uint8_t processedInterfaces[USB_HOST_CONFIG_CONFIGURATION_MAX_INTERFACE] = {0}; switch (eventCode & 0x0000FFFFU) { case kUSB_HostEventAttach: status1 = USB_HostInterface0CicVcomEvent(deviceHandle, configurationHandle, eventCode, processedInterfaces); status2 = USB_HostInterface0HidMouseEvent(deviceHandle, configurationHandle, eventCode, processedInterfaces); if ((status1 == kStatus_USB_NotSupported) && (status2 == kStatus_USB_NotSupported)) { status = kStatus_USB_NotSupported; } break; case kUSB_HostEventNotSupported: usb_echo("Device not supported.\r\n"); break; case kUSB_HostEventEnumerationDone: status1 = USB_HostInterface0CicVcomEvent(deviceHandle, configurationHandle, eventCode, processedInterfaces); status2 = USB_HostInterface0HidMouseEvent(deviceHandle, configurationHandle, eventCode, processedInterfaces); if ((status1 != kStatus_USB_Success) && (status2 != kStatus_USB_Success)) { status = kStatus_USB_Error; } break; case kUSB_HostEventDetach: status1 = USB_HostInterface0CicVcomEvent(deviceHandle, configurationHandle, eventCode, processedInterfaces); status2 = USB_HostInterface0HidMouseEvent(deviceHandle, configurationHandle, eventCode, processedInterfaces); if ((status1 != kStatus_USB_Success) && (status2 != kStatus_USB_Success)) { status = kStatus_USB_Error; } break; case kUSB_HostEventEnumerationFail: usb_echo("Enumeration failed\r\n"); break; default: break; } return status; } USB_HostTasks() is used to deal with all the USB messages in the main loop. At last, HID work should also be added in this function. void USB_HostTasks(void) { USB_HostTaskFn(g_HostHandle[0]); USB_HostTaskFn(g_HostHandle[1]); USB_HostInterface0CicVcomTask(); USB_HostInterface0HidMouseTask(); }   After all these steps, the dual USB function is ready. User can insert USB mouse and USB CDC device into any of the two USB port simultaneously. Conclusion All the RT/LPC/Kinetis devices with two OTG or HOST can support dual USB host. With the help of MCUXpresso Config Tool, it is easy to implement this function.
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Goal Our goal is to train a model that can take a value, x, and predict its sine, y. In a real-world application, if you needed the sine of x, you could just calculate it directly. However, by training a model to approximate the result, we can demonstrate the basics of machine learning. TensorFlow and Keras TensorFlow is a set of tools for building, training, evaluating, and deploying machine learning models. Originally developed at Google, TensorFlow is now an open-source project built and maintained by thousands of contributors across the world. It is the most popular and widely used framework for machine learning. Most developers interact with TensorFlow via its Python library. TensorFlow does many different things. In this post, we’ll use Keras, TensorFlow’s high-level API that makes it easy to build and train deep learning networks. To enable TensorFlow on mobile and embedded devices, Google developed the TensorFlow Lite framework. It gives these computationally restricted devices the ability to run inference on pre-trained TensorFlow models that were converted to TensorFlow Lite. These converted models cannot be trained any further but can be optimized through techniques like quantization and pruning. Building the Model To building the Model, we should follow the below steps. Obtain a simple dataset. Train a deep learning model. Evaluate the model’s performance. Convert the model to run on-device. Please navigate to the URL in your browser to open the notebook directly in Colab, this notebook is designed to demonstrate the process of creating a TensorFlow model and converting it to use with TensorFlow Lite. Deploy the mode to the RT MCU Hardware Board: MIMXRT1050 EVK Board Fig 1 MIMXRT1050 EVK Board Template demo code: evkbimxrt1050_tensorflow_lite_cifar10 Code /* Copyright 2017 The TensorFlow Authors. All Rights Reserved. Copyright 2018 NXP. All Rights Reserved. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. ==============================================================================*/ #include "board.h" #include "pin_mux.h" #include "clock_config.h" #include "fsl_debug_console.h" #include <iostream> #include <string> #include <vector> #include "timer.h" #include "tensorflow/lite/kernels/register.h" #include "tensorflow/lite/model.h" #include "tensorflow/lite/optional_debug_tools.h" #include "tensorflow/lite/string_util.h" #include "Sine_mode.h" int inference_count = 0; // This is a small number so that it's easy to read the logs const int kInferencesPerCycle = 30; const float kXrange = 2.f * 3.14159265359f; #define LOG(x) std::cout void RunInference() { std::unique_ptr<tflite::FlatBufferModel> model; std::unique_ptr<tflite::Interpreter> interpreter; model = tflite::FlatBufferModel::BuildFromBuffer(sine_model_quantized_tflite, sine_model_quantized_tflite_len); if (!model) { LOG(FATAL) << "Failed to load model\r\n"; exit(-1); } model->error_reporter(); tflite::ops::builtin::BuiltinOpResolver resolver; tflite::InterpreterBuilder(*model, resolver)(&interpreter); if (!interpreter) { LOG(FATAL) << "Failed to construct interpreter\r\n"; exit(-1); } float input = interpreter->inputs()[0]; if (interpreter->AllocateTensors() != kTfLiteOk) { LOG(FATAL) << "Failed to allocate tensors!\r\n"; } while(true) { // Calculate an x value to feed into the model. We compare the current // inference_count to the number of inferences per cycle to determine // our position within the range of possible x values the model was // trained on, and use this to calculate a value. float position = static_cast<float>(inference_count) / static_cast<float>(kInferencesPerCycle); float x_val = position * kXrange; float* input_tensor_data = interpreter->typed_tensor<float>(input); *input_tensor_data = x_val; Delay_time(1000); // Run inference, and report any error TfLiteStatus invoke_status = interpreter->Invoke(); if (invoke_status != kTfLiteOk) { LOG(FATAL) << "Failed to invoke tflite!\r\n"; return; } // Read the predicted y value from the model's output tensor float* y_val = interpreter->typed_output_tensor<float>(0); PRINTF("\r\n x_value: %f, y_value: %f \r\n", x_val, y_val[0]); // Increment the inference_counter, and reset it if we have reached // the total number per cycle inference_count += 1; if (inference_count >= kInferencesPerCycle) inference_count = 0; } } /* * @brief Application entry point. */ int main(void) { /* Init board hardware */ BOARD_ConfigMPU(); BOARD_InitPins(); BOARD_InitDEBUG_UARTPins(); BOARD_BootClockRUN(); BOARD_InitDebugConsole(); NVIC_SetPriorityGrouping(3); InitTimer(); std::cout << "The hello_world demo of TensorFlow Lite model\r\n"; RunInference(); std::flush(std::cout); for (;;) {} } ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ Test result On the MIMXRT1050 EVK Board, we log the input data: x_value and the inferenced output data: y_value via the Serial Port. Fig2 Received data In a while loop function, It will run inference for a progression of x values in the range 0 to 2π and then repeat. Each time it runs, a new x value is calculated, the inference is run, and the data is output. Fig3 Test result In further, we use Excel to display the received data against our actual values as the below figure shows. Fig4 Dot Plot You can see that, for the most part, the dots representing predicted values form a smooth sine curve along the center of the distribution of actual values. In general, Our network has learned to approximate a sine curve.
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INTRODUCTION REQUIREMENTS INTEGRATION     1. INTRODUCTION   This document provides an step-by-step guide to migrate the webcam application explained on AN12103 "Developing a simple UVC device based on i.MX RT1050" to EVKB-MIMXRT1050. The goal is getting the application working on rev. B silicon, using the current SDK components (v2.4.2) and with MCUXpresso IDE (v10.2.1), because the original implementation from the application note is using rev. A silicon and is developed on IAR IDE.   2. REQUIREMENTS   A) Download and install MCUXpresso IDE v10.2.1. B) Build an MCUXpresso SDK v2.4.2 for EVKB-MIMXRT1050 from the "SDK Builder web page", ensuring that CSI and USB components are included, and MCUXpresso IDE is selected, and install it. For A) and B) steps, you could refer to the following Community document: https://community.nxp.com/docs/DOC-341985  C) Download the source code related to AN12103. D) Having the EVKB-MIMXRT1050 board, with MT9M1114 camera module. 3. INTEGRATION   a) Open MCUXpresso IDE, and click on "Import SDK example" shortcut, select the "evkbimxrt1050" board and click on "Next" button. b) Select the "driver_examples->csi->csi_rgb565" and "usb_examples->dev_video_virtual_camera_bm" examples, and click on "Finish" button. c) Copy the "fsl_csi.h", "fsl_csi.c", "fsl_lpi2c.h" and "fsl_lpi2c.c" files from the "drivers" folder of CSI project, to the "drivers" folder of the Virtual_Camera project. d) Copy the "pin_mux.h" and "pin_mux.c" files from the "board" folder of CSI project, to the "board->src" folder of the Virtual_Camera project, replacing the already included files. e) Copy the "camera" folder from AN12103 software package from the path below, to the Virtual_Camera project: <AN12103SW\boards\evkmimxrt1050\user_apps\uvc_demo\src\camera> Also copy the "main.c" file from AN12103 software package to the "sources" folder of the Virtual_Camera project. Ensure selecting the option "Copy files and folders" when copying folders/files. f) Right click on the recently added "camera" folder, and select "Properties". Then, on the "C/C++ Build" menu, remove the checkbox "Exclude resource from build" option, and then click on "Apply and Close" button. g) Right click on the Virtual_Camera project, and select "Properties". Then, select the "C/C++ Build -> Settings -> MCU C Compiler -> Preprocessor" menu, and click on the "+" button to add the following value: "SDK_I2C_BASED_COMPONENT_USED=1", and click on "OK" button. h) Now, move to the "Includes" menu of the same window, and click on the "+" button to add the following value: "../camera". Repeat the same procedure on "MCU Assembler -> General" menu, and then, click on "Apply and Close" button. i) Refer to "usb" folder from AN12103 software package from the path below, and copy "video_camera.h", "video_camera.c", "usb_device_descriptor.h" and "usb_device_descriptor.c" files to the "sources" folder of Virtual_Camera project, ensuring selecting the option "Copy files and folders" and overwriting the already included files: <AN12103SW\boards\evkmimxrt1050\user_apps\uvc_demo\src\usb> j) Select "video_data.h", "video_data.c", "virtual_camera.h" and "virtual_camera.c" files and "doc" folder, then right click and select "Delete". Click on "OK" button of the confirmation window to remove these resources from the Virtual_Camera project. k) Refer to "fsl_mt9m114.c" file from "camera" folder of Virtual_Camera project, and delete the "static" definition from functions "MT9M114_Init", "MT9M114_Deinit", "MT9M114_Start", "MT9M114_Stop", "MT9M114_Control" and "MT9M114_InitExt". l) Refer to "main.c" file from "sources" folder of Virtual_Camera project, and comment out the call to the function "BOARD_InitLPI2C1Pins". Also, refer to "board.c" file from "board->src" folder of Virtual_Camera project, and comment out the call to the function "SCB_EnableDCache". m) Refer to "camera_device.c" file from "camera" folder of Virtual_Camera project, and comment out the line "AT_NONCACHEABLE_SECTION_ALIGN(static uint16_t s_cameraFrameBuffer[CAMERA_FRAME_BUFFER_COUNT][CAMERA_VERTICAL_POINTS * CAMERA_HORIZONTAL_POINTS + 32u], FRAME_BUFFER_ALIGN);" and add the following line: static uint16_t __attribute__((section (".noinit.$BOARD_SDRAM"))) s_cameraFrameBuffer[CAMERA_FRAME_BUFFER_COUNT][CAMERA_VERTICAL_POINTS * CAMERA_HORIZONTAL_POINTS + 32u] __attribute__ ((aligned (FRAME_BUFFER_ALIGN))); n) Compile and download the application into the EVKB-MIMXRT1050 board. The memory usage is shown below: o) When running the application, if you also have the serial terminal connected, you should see the print message. Additionally, if connected to Windows OS, you could find it as "CSI Camera Device" under the "Imaging devices" category. p) Optionally, you could rename the Virtual_Camera project to any other desired name, with rigth click on Project, and selecting "Rename" option, and finally, click on "OK" button. It is also attached the migrated MCUXpresso IDE project including all the steps mentioned on the present document. Hope this will be useful for you. Best regards! Some additional references: https://community.nxp.com/thread/321587  Defining Variables at Absolute Addresses with gcc | MCU on Eclipse   
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The path of SDRAM Clock in Clock Tree                 According CCM clock tree in i.MXRT1050 reference manual, we can abstract part of SDRAM clock, and draw it’s diagram below.   Descriptions for Diagram 1 (1) PLL2 PFD2                 ① Registers related to PLL2 PFD2 ---CCM_ANALOG_PLL_SYSn (page 767, in reference manual) Address: 0x400D_8030h important bits: bit[15:14]---- select clock source. Bit[13] ----- Enable PLL output Bit[0]------- This field controls the PLL loop divider. 0 - Fout=Fref*20; 1 - Fout=Fref*22. ---CCM_ANALOG_PLL_SYS_NUM(page 768, in reference manual) Address: 0x400D_8050h important bits: bit[29:0]--- 30 bit numerator (A) of fractional loop divider (signed integer) ---CCM_ANALOG_PLL_SYS_DENOM (page 769, in reference manual) Address: 0x400D_8060h important bits: bit[29:0]---- 30 bit Denominator (B) of fractional loop divider (unsigned integer).   ---CCM_ANALOG_PFD_528n (page 769, in reference manual) Address: 0x400D_8100h important bits: bit[21:16]----- This field controls the fractional divide value. The resulting frequency shall be 528*18/PFD2_FRAC where PFD2_FRAC is in the range 12-35.   ② Computational formula PLL2_PFD2_OUT=(External 24MHz)*(Fout + A/B) * 18/ PFD2_FRAC   ③ Example for PLL2_PFD2_OUT computation CCM_ANALOG_PLL_SYSn[0] = 1  // Fout=Fref*22 CCM_ANALOG_PLL_SYS_NUM[29:0] = 56  // A = 56 CCM_ANALOG_PLL_SYS_DENOM[29:0] = 256  // B=256 CCM_ANALOG_PFD_528n[21:16] = 29                       // PFD2_FRAC=29   PLL2_PFD2_OUT = 24 * (22 + 56/256)*18/29 = 331MHz (330.98MHz)   (2) Clock Select Register : CCM_CBCDR Address: 0x 400F_C014h important bits: SEMC_ALT_CLK_SEL & SEMC_CLK_SEL & SEMC_PODF bit[7] --- bit[SEMC_ALT_CLK_SEL] 0---PLL2 PFD2 will be selected as alternative clock for SEMC root clock 1---PLL3 PFD1 will be selected as alternative clock for SEMC root clock Bit[6] --- bit[SEMC_CLK_SEL] 0----Periph_clk output will be used as SEMC clock root 1----SEMC alternative clock will be used as SEMC clock root Bit[18:16] --- bit[SEMC_PODF] Post divider for SEMC clock. NOTE: Any change of this divider might involve handshake with EMI. See CDHIPR register for the handshake busy bits. 000 divide by 1 001 divide by 2 010 divide by 3 011 divide by 4 100 divide by 5 101 divide by 6 110 divide by 7 111 divide by 8 Example for configuration of SDRAM Clock   Example : 166MHz SDRAM Clock   ---- 0x400D8030 = 0x00002001 // wirte  0x00002001 to CCM_ANALOG_PLL_SYSn ---- 0x400D8050 = 0x00000038 // write 0x00000038 to CCM_ANALOG_PLL_SYS_NUM ---- 0x400D8060 = 0x00000100 // write 0x00000100 to CCM_ANALOG_PLL_SYS_DENOM ---- 0x400D8100 = 0x001d0000 // write 0x001d0000 to CCM_ANALOG_PFD_528n ---- 0x400FC014 = 0x00010D40 // write 0x00010D40 to CCM_CBCDR, divided by 2         NXP TIC team Weidong Sun 2018-06-01
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RT1050 SDRAM app code boot from SDcard burn with 3 tools Abstract       This document is about the RT series app running on the external SDRAM, but boot from SD card. The content contains SDRAM app code generate with the RT1050 SDK MCUXpresso IDE project, burn the code to the external SD card with flashloader MFG tool, and MCUXPresso Secure Provisioning. The MCUBootUtility method can be found from this post: https://community.nxp.com/docs/DOC-346194       Software and Hardware platform: SDK 2.7.0_EVKB-IMXRT1050 MCUXpresso IDE MXRT1050_GA MCUBootUtility MCUXPresso Secure Provisioning MIMXRT1050-EVKB 2 RT1050 SDRAM app image generation     Porting SDK_2.7.0_EVKB-IMXRT1050 iled_blinky project to the MCUXPresso IDE, to generate the code which is located in SDRAM, the configuration is modified like the following items:       2.1 Copy code to RAM 2.2  Modify memory location to SDRAM address 0X80002000 The code which boots from SD card and running in the SDRAM is the non-xip code, so the IVT offset is 0X400, in our test, we put the image from the SDRAM memory address 0x800002000, the configuration is: 2.3 Modify the symbol 2.4 Generate the .s19 file      After build has no problems, then generate the app.s19 file:   Rename the app.19 image file to evkbimxrt1050_iled_blinky_sdram_0x2000.s19, and copy it to the flashloader folder: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\elftosb\win   3, Flashloader configuration and download    This chapter will use flashloader to configure the image which can download the SDRAM app code to the external SD card with MFGTool.       We need to prepare the following files: SDRAM interface configuration file CFG_DCD.bin imx-sdram-unsigned-dcd.bd program_sdcard_image.bd 3.1 SDRAM DCD file preparation      MIMXRT1050-EVKB on board SDRAM is IS42S16160J, we can use the attached dcd_model\ISSI_IS42S16160J\dcd.cfg and dcdgen.exe tool to generate the CFG_DCD.bin, the commander is: dcdgen -inputfile=dcd.cfg -bout -cout   Copy CFG_DCD.bin file to the flashloader path: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\elftosb\win 3.2 imx-sdram-unsigned-dcd.bd file Prepare the imx-sdram-unsigned-dcd.bd file content as: options {     flags = 0x00;     startAddress = 0x80000000;     ivtOffset = 0x400;     initialLoadSize = 0x2000;     DCDFilePath = "CFG_DCD.bin";     # Note: This is required if the default entrypoint is not the Reset_Handler     #       Please set the entryPointAddress to Reset_Handler address     entryPointAddress = 0x800022f1; }   sources {     elfFile = extern(0); }   section (0) { }  The above entrypointAddress data is from the .s19 reset handler(0X80002000+4 address data): Copy imx-sdram-unsigned-dcd.bd file to flashloader path: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\elftosb\win Open cmd, run the following command: elftosb.exe -f imx -V -c imx-sdram-unsigned-dcd.bd -o ivt_evkbimxrt1050_iled_blinky_sdram_0x2000.bin evkbimxrt1050_iled_blinky_sdram_0x2000.s19 After running the command, two app IVT files will be generated: 3.3 program_sdcard_image.bd file Prepare the program_sdcard_image.bd file content as: # The source block assign file name to identifiers sources {  myBootImageFile = extern (0); }   # The section block specifies the sequence of boot commands to be written to the SB file section (0) {       #1. Prepare SDCard option block     load 0xd0000000 > 0x100;     load 0x00000000 > 0x104;       #2. Configure SDCard     enable sdcard 0x100;       #3. Erase blocks as needed.     erase sdcard 0x400..0x14000;       #4. Program SDCard Image     load sdcard myBootImageFile > 0x400;         #5. Program Efuse for optimal read performance (optional)     # Note: It is just a template, please program the actual Fuse required in the application     # and remove the # to enable the command     #load fuse 0x00000000 > 0x07;   } Copy program_sdcard_image.bd to the flashloader path: Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\elftosb\win Open cmd, run the following command: elftosb.exe -f kinetis -V -c program_sdcard_image.bd -o boot_image.sb ivt_evkbimxrt1050_iled_blinky_sdram_0x2000_nopadding.bin Copy the generated boot_image.sb file to the following flashloader path: \Flashloader_i.MXRT1050_GA\Flashloader_RT1050_1.1\Tools\mfgtools-rel\Profiles\MXRT105X\OS Firmware 3.4 MFGTool burn code to SD card    Prepare one SD card, insert it to J20, let the board enter the serial download mode, SW7:1-ON 2-OFF 3-OFF 4-ON. Find two USB cable, one is connected to J28, another is connected to J9, we use the HID to download the image.    Open MFGTool.exe, and click the start button:          Modify the boot mode to internal boot, and boot from the external SD card, SW7:1-ON 2-OFF 3-ON 4-OFF.      Power off and power on the board again, you will find the onboard LED D18 is blinking, it means the external SDRAM APP code is boot from external SD card successfully. 4, MCUBootUtility configuration and code download    Please check this community document: https://community.nxp.com/docs/DOC-346194     Here just give one image readout memory map, it will be useful to understand the image location information:     After download, we can readout the SD card image, from 0X400 is the IVT, BD, DCD data, from 0X1000 is the image which is the same as the app.s19 file.     5, MCUXpresso Secure Provisioning configuration and download   This software is released in the NXP official website, it is also the GUI version, which can realize the normal code and the secure code downloading, it will be more easy to use than the flashloader tool, customer don’t need to input the command, the tool help the customer to do it, the function is similar to the MCUBootUtility, MCUBootUtility tool is the opensource tool which is shared in the github, but is not released in the NXP official website.   Now, we use the new official realized tool to download the SDRAM app code to the external SD card, the board still need to enter the serial download mode, just like the flashloader and the MCUBootUtility too, the detail operation is:  We can find this tool is also very easy to use, customer still need to provide the app.19 and the dcd.bin, then give the related boot device configuration is OK.    After the code is downloaded successfully, modify the boot mode to internal boot, and boot from the external SD card, SW7:1-ON 2-OFF 3-ON 4-OFF.     Power off and power on the board again, you will find the onboard LED D18 is blinking, it means the external SDRAM APP code is boot from external SD card successfully.   Until now, all the three methods to download the SDRAM app code to the SD card is working, flashloader is the command based tool, MCUBootUtility and MCUXPresso Secure Provisioning is the GUI tool, which is more easy to use.        
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Overview ======== The LPUART example for FreeRTOS demonstrates the possibility to use the LPUART driver in the RTOS with hardware flow control. The example uses two instances of LPUART IP and sends data between them. The UART signals must be jumpered together on the board. Toolchain supported =================== - MCUXpresso 11.0.0 Hardware requirements ===================== - Mini/micro USB cable - MIMXRT1050-EVKB board - Personal Computer Board settings ============== R278 and R279 must be populated, or have pads shorted. These resistors are under the display opposite side of board from uSD connector. The following pins need to be jumpered together: --------------------------------------------------------------------------------- | | UART3 (UARTA) | UART8 (UARTB) | |---|-------------------------------------|-------------------------------------| | # | Signal | Function | Jumper | Jumper | Function | Signal | |---|---------------|----------|----------|----------|----------|---------------| | 1 | GPIO_AD_B1_07 | RX | J22-pin1 | J23-pin1 | TX | GPIO_AD_B1_10 | | 2 | GPIO_AD_B1_06 | TX | J22-pin2 | J23-pin2 | RX | GPIO_AD_B1_11 | | 3 | GPIO_AD_B1_04 | CTS | J23-pin3 | J24-pin5 | RTS | GPIO_SD_B0_03 | | 4 | GPIO_AD_B1_05 | RTS | J23-pin4 | J24-pin4 | CTS | GPIO_SD_B0_02 | --------------------------------------------------------------------------------- Prepare the Demo ================ 1. Connect a USB cable between the host PC and the OpenSDA USB port on the target board. 2. Open a serial terminal with the following settings: - 115200 baud rate - 8 data bits - No parity - One stop bit - No flow control 3. Download the program to the target board. 4. Either press the reset button on your board or launch the debugger in your IDE to begin running the demo. Running the demo ================ You will see status of the example printed to the console. Customization options =====================
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Source code: https://github.com/JayHeng/NXP-MCUBootUtility 【v1.3.0】 Features: > 1. Can generate .sb file by actions in efuse operation utility window >    支持生成仅含自定义efuse烧写操作(在efuse operation windows里指定)的.sb格式文件 Improvements: > 1. HAB signed mode should not appliable for FlexSPI/SEMC NOR device Non-XIP boot with RT1020/1015 ROM >    HAB签名模式在i.MXRT1020/1015下应不支持从FlexSPI NOR/SEMC NOR启动设备中Non-XIP启动 > 2. HAB encrypted mode should not appliable for FlexSPI/SEMC NOR device boot with RT1020/1015 ROM >    HAB加密模式在i.MXRT1020/1015下应不支持从FlexSPI NOR/SEMC NOR启动设备中启动 > 3. Multiple .sb files(all, flash, efuse) should be generated if there is efuse operation in all-in-one action >    当All-In-One操作中包含efuse烧写操作时,会生成3个.sb文件(全部操作、仅flash操作、仅efuse操作) > 4. Can generate .sb file without board connection when boot device type is NOR >    当启动设备是NOR型Flash时,可以不用连接板子直接生成.sb文件 > 5. Automatic image readback can be disabled to save operation time >    一键操作下的自动程序回读可以被禁掉,用以节省操作时间 > 6. The text of language option in menu bar should be static and easy understanding >    菜单栏里的语言选项标签应该是静态且易于理解的(中英双语同时显示) Bugfixes: > 1. Cannot generate bootable image when original image (hex/bin) size is larger than 64KB >    当输入的源image文件格式为hex或者bin且其大小超过64KB时,生成可启动程序会失败 > 2. Cannot download large image file (eg 6.8MB) in some case >    当输入的源image文件非常大时(比如6.8MB),下载可能会超时失败 > 3. There is language switch issue with some dynamic labels >    当切换显示语言时,有一些控件标签(如Connect按钮)不能实时更新 > 4. Some led demos of RT1050 EVKB board are invalid >    /apps目录下RT1050 EVKB板子的一些LED demo是无效的 【v1.4.0】 Features: > 1. Support for loading bootable image into uSDHC SD/eMMC boot device >    支持下载Bootable image进主动启动设备 - uSDHC接口SD/eMMC卡 > 2. Provide friendly way to view and set mixed eFuse fields >    支持更直观友好的方式去查看/设置某些混合功能的eFuse区域 Improvements: > 1. Set default FlexSPI NOR device to align with NXP EVK boards >    默认FlexSPI NOR device应与恩智浦官方EVK板卡相匹配 > 2. Enable real-time gauge for Flash Programmer actions >    为通用Flash编程器里的操作添加实时进度条显示
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Introduction NXP i.MX RT1xxx series provide the High Assurance Boot (HAB) feature which makes the hardware to have a mechanism to ensure that the software can be trusted, as the HAB feature enables the ROM to authenticate the program image by using digital signatures, which can assure the application image's integrity, authenticated and undeniable. So the OEM can utilize it to make their product reject any system image which is not authorized to run. However, what's the trust chain of HAB for implementing the purpose? How the key and certificate generate In the installation directory of MCUXpresso Secure Provisioning:  ~\nxp\MCUX_Provi_v3.1\bin\tools_scripts\keys , there are scripts for generating keys: hab4_pki_tree.sh and hab4_pki_tree.bat (both are applicable to Linux and Windows systems respectively), running any of the above scripts will generate 13 pairs of public and private keys in sequence through OpenSSL, which constitute the below tree structure. Fig1 Key Tree structure The public key and private key generated by OpenSSL are paired one by one, saving the private key and publishing the corresponding public key to the outside world can easily implement asymmetric encryption applications. But how to ensure that the obtained public key is correct and has not been tampered with? At this time, the intervention of authoritative departments is required. Just like everyone can print their resume and say who they are, but if they have the seal of the Public Security Bureau, only the household registration book can prove you are you. This issued by the authority is called a certificate. What's in the certificate? Of course, it should contain a public key, which is the most important; there is also the owner of the certificate, just like the household registration book with your name and ID number, indicating that the book is yours; in addition, there is the issuer of the certificate and the validity period of the ID card is a bit like the issuer institution on the ID card, and how many years of the validity period. If someone fakes a certificate issued by an authority, it's like having fake ID cards and fake household registration books. To generate a certificate, you need to initiate a certificate request, and then send the request to an authority for certification, which is called a CA(Certificate Authority). After sending this request to the authority, the authority will give the certificate a signature. Another question arises, how can the signature be guaranteed to be signed by a genuine authority? Of course, it can only be signed with something that is only in the hands of the authority, which is the CA's private key. The signature algorithm probably works like this: a Hash calculation is performed on the target information to obtain a Hash value. And this process is irreversible, that is to say, the original information content cannot be obtained through the Hash value. When the information is sent out, the hash value is encrypted and sent together with the information as a signature. The process is as follows. Fig2 Signature and verification process Looking at the content of the certificate (as shown below), we will find that there is an Issuer, that is, who issued the certificate; The subject is to who the certificate is issued; Validity is the certificate period; Public-key is the content of the public key, and related signature algorithm. You will find that in order to verify the certificate, the public key of the CA is required. Then a new question arises. How can we be sure that the public key of the CA is correct? This requires a superior CA to sign the CA's public key, and then form the CA's certificate. If you want to know whether a CA's certificate is reliable, you need to see if the public key of the CA's superior certificate can unlock the CA's signature. Just likes if you don’t trust the District Public Security Bureau, you can call the Municipal Public Security Bureau and ask the Municipal Public Security Bureau to confirm its legitimacy of the District Public Security Bureau. This goes up layer by layer until the root CA makes the final endorsement. Through this layer-by-layer credit endorsement method, the normal operation of the asymmetric encryption mode is guaranteed. How does the Root CA prove itself? At this time, Root CA will issue another certificate (as shown below), called the Self-Signed Certificate, which is to sign itself with its own private key, giving people a feeling of "I am me, whether you believe it or not", Therefore, its format content is slightly different from the above CA certificate. Its Issuer and Subject are the same, and its own public key can be used for authentication. So the certificate authentication process will also end here. In this way, in addition to generating the public key and private key through running the script, the OpenSSL will also generate the certificate chain shown below.  Fig3 certificates Boot flow of the HAB mode Figure 4 shows the boot flow of the HAB mode. And steps 1, 2, and 3 are essentially the signature verification process. Fig4 Boot flow of the HAB mode The verification process (as shown in Figure 2) can be used to detect data integrity, identity authentication, and non-repudiation when the public key is trusted, so hab4_pki_tree.sh and hab4_pki_tree.bat scripts can ensure the generated public key and private key pair and the certificate are trusted, it's the "perfectly closed loop". However, the Application image in Figure 4 is plaintext, and the confidentiality of the data is not implemented, so the encrypted boot is always a combination of the HAB boot and the encrypted boot is an advanced usage of an authenticated boot. Reference AN4581: i.MX Secure Boot on HABv4 Supported Devices AN12681: How to use HAB secure boot in i.MX RT10xx  
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A small project I worked on was to understand how RT1050 boot-up performs from different memory types. I used the LED_blinky code from the SDK as a baseline, and ran some tests on the EVKB board. The data I gathered is described below, as well as more detailed testing procedures. Testing Procedure The boot-up time will be defined as the time from which the processor first receives power, to when it executes the first line of code from the main() function. Time was measured using an oscilloscope (Tektronix TDS 2014) between the rising edge of the POR_B* signal to the following two points: FlexSPI_CS asserted (first read of the FlexSPI by the ROM)** GPIO Toggle in application code (signals beginning of code execution).*** *The POR_B signal was available to scope through header J26-1 **The FlexSPI_CS signal is available through a small pull-up resistor on the board, R356. A small wire was soldered alongside this resistor, and was probed on the oscilloscope. ***The GPIO pin that was used was the same one that connected to USER_LED (Active low). This pin could be scoped through header J22-5. TP 2, 3, 4, and 5 are used to ground the probe of the oscilloscope. This was all done in the EVKB evaluation board. Here are a couple of noteworthy points about the test ran: This report mostly emphasizes the time between the rise of the POR_B signal, and the first line of execution of code. However, there is a time between when power is first provided to the board and the POR_B system goes up. This is a matter of power electronics and can vary depending on the user application and design. Because of this, this report will not place a huge emphasis on this. The first actual lines of code of the application is actually configuring several pins of the processor. Only after these pins are executed, does the GPIO toggle low and the time is taken on the oscilloscope. However, these lines of configuration code are executed so rapidly, that the time is ignored for the test.   Clock Configurations The bootable image was flashed to the RT1050 in all three cases. Afterwards, in MCUXpresso, the debugger was configured with “Attach Only” set to true. A debug session was then launched, and after the processor finished executing code, it was paused and the register values were read according to the RT1050 Reference Manual, chapter 18, CCM Block Diagram.  Boot Configuration: Core Clock (MHz) * FlexSPI Clock (MHz) SEMC Clock (MHz) FlexSPI 130 99 SDRAM 396 130 99 SRAM 396 130 99 *The Core Clock speed was also verified by configuring clko1 as an output with the clock speed divided by 8. This frequency was measured using an oscilloscope and verified to be 396 MHz. Results The time to chip select pin represents the moment when the first flash read happens from the RT1050 processor. The time to GPIO output represents the boot-up time.   As expected, XiP Hyperflash boots faster than other memories. SRAM and SDRAM memories must copy to executable memory before executing which will take more time and therefore boot slower. In the sections below, a more thorough explanation is provided of how these tests were ran and why Hyperflash XiP is expected to be the fastest. Hyperflash XiP Boot Up Below is an outline of the steps of what we expect the Hyperflash XiP boot-up process to look like: Power On Reset (J26-1) Begin access to Flash memory (FlexSPI_SS0) Execute in place in flash (XiP) First line of code is exectuted (USER_LED) In MCUXpresso, the map file showed the following: The oscilloscope image is below:   SDRAM Boot Up The processor will bootup from ROM, which will be told to copy an application image from the serial NOR flash memory to SDRAM (serial NOR flash uses Hyperflash communication). The RT flashloader tool will let me load up the application to the flash to be configured to copy over memory to the SDRAM and execute to it.   It is expected that copying to SDRAM will be slower than executing in place from Hyperflash since an entire copying action must take place.   The SDRAM boot-up process looks like the following: Power On Reset (J26-1) Begin access to Flash memory (FlexSPI_SS0) Copy code to SDRAM Execute in place in SDRAM (FlexSPI_SS0) First line of code is executed (USER_LED)   In MCUXpresso, the map file showed the following:   In order to run this test, I followed these instructions: https://community.nxp.com/docs/DOC-340655. SRAM Boot Up For SRAM, a similar process to that of SDRAM is expected. The processor will first boot from internal ROM, and then go to Hyperflash. It will then copy over everything from Hyperflash to internal SRAM DTC memory and then execute from there.  The SRAM Boot Up Process follows as such: Power On Reset (J26-1) Begin access to Flash memory (FlexSPI_SS0) Copy code to SRAM Execute in place in SRAM (FlexSPI_SS0) First line of code is executed (USER_LED)   In MCUXpresso, the map file showed the following:   This document was generated from the following discussion: javascript:;
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