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Purpose: Introduce how to debug M4 using trace32 and the difference with general debug case.If you are using other jtag debug tools, maybe you need to do the similar configuration. Debug tools: Trace32 – you can refer to http://www.lauterbach.cn/ for more information about this tool. Firmware: Here we using Freertos as the example, but not limited to this. There is one small difference with general debug case to M4 in 6sx, which when you attach M4 and break M4, it may impact the peripheral that A9 is using. You may have found when you break M4, A9 uart console also was frozen at the same time. This is caused by that when M4 enter debug mode, the debug_req will also assert in the peripherals which you are using on the A9 system. So,need configure the peripherals to keep running when the debug_req is assert when do the M4/A9 debug separately. Need configure the DBGEN (*) register in the related peripherals to allow the eripherals not going into debug mode and keep running even if debug_req is HIGH. The peripherals we need take care are: CAN, UART, EPIT,GPT, ENET, PWM. Note: For the CAN, the register bit is called FRZ Here is the details of uart dbgen in the RM: So if we want debug M4 separately,we should disable this bit, as A9 was using this peripheral. Here we take Freertos as the example to illuminate how to debug M4 step by step: Enable DBGEN case: Load M4 image into memory and kick off M4. (You can refer to for the details) =>fatload mmc 2:1 0x9ff00000 hello_world_ddr.bin reading hello_world_ddr.bin 18748 bytes read in 30 ms (609.4 KiB/s) =>dcache flush =>bootaux 0x9ff00000 ##Starting auxiliary core at 0x9FF00000 ... Attach M4 using the m4.cmm file(attached): Note: You can find the elf file at the same folder of binary: So now you can debug your code step by step.If you go back to A9 side uart console, you would find the console have been frozen. Disable DBGEN case at A9 side: Load M4 image into memory and kick off M4. (You can refer to for imx6sx user guide the details) =>mm 0x20200b4 020200b4:00000020 ? 0x820 =>fatload mmc 2:1 0x9ff00000 hello_world_ddr.bin reading hello_world_ddr.bin 18748 bytes read in 30 ms (609.4 KiB/s) =>dcache flush =>bootaux 0x9ff00000 ##Starting auxiliary core at 0x9FF00000 ... Attach M4 using the m4.cmm file(attached) In this case you will the A9 uart console still can work, after you break M4. Disable DBGEN case at M4 side: Load M4 image into memory and kick off M4. =>fatload mmc 2:1 0x9ff00000 hello_world_ddr.bin reading hello_world_ddr.bin 18748 bytes read in 30 ms (609.4 KiB/s) =>dcache flush =>bootaux 0x9ff00000 ##Starting auxiliary core at 0x9FF00000 Attach M4 using the m4_disable_dbgen.cmm file(attached) In this case you will the A9 uart console still can work, after you break M4. Notes: For more trace32 usage, please refer to http://www.lauterbach.cn/ For more imx6sx information, please refer to i.MX 6SoloX Family of Applications Processors|NXP.

Overview This document introduces how to setup i.MX6Dual/Quad and i.MX6Solo/DualLite Linux software for PCIe compliance test. Software Baselines i.MX6Dual/Quad: Linux BSP L2.6.35_1.0.0 i.MX6Solo/DualLite: Linux BSP L2.6.35_2.0.0 Software Changes To enable PCIe compliance test, PCIe software driver should not turn off PCIe clock and power in the tests. So the following changes are required: diff --git a/arch/arm/mach-mx6/pcie.c b/arch/arm/mach-mx6/pcie.c index 26d26f2..ad71085 100644 --- a/arch/arm/mach-mx6/pcie.c +++ b/arch/arm/mach-mx6/pcie.c @@ -801,6 +801,7 @@ static void __init add_pcie_port(void __iomem *base, void __iomem *dbi_base, } else { pr_info("IMX PCIe port: link down!\n"); +#if 0 /* Release the clocks, and disable the power */ pcie_clk = clk_get(NULL, "pcie_clk"); if (IS_ERR(pcie_clk)) @@ -820,6 +821,7 @@ static void __init add_pcie_port(void __iomem *base, void __iomem *dbi_base, imx_pcie_clrset(IOMUXC_GPR1_TEST_POWERDOWN, 1 << 18, IOMUXC_GPR1); +#endif } } Software Build Integrate the patch to the baseline code and recompile the kernel by following the instructions in Linux BSP user guide. Before recompile, please ensure the following configuration is enabled by selecting " System Type -> Freescale MXC Implementations -> PCI Express support" as "*": # MX6 Options: # CONFIG_IMX_PCIE=y

DirectFB DirectFB is a thin library that provides hardware graphics acceleration, input device handling and abstraction, integrated windowing system with support for translucent windows and multiple display layers, not only on top of the Linux Framebuffer Device. It is a complete hardware abstraction layer with software fallbacks for every graphics operation that is not supported by the underlying hardware. DirectFB adds graphical power to embedded systems and sets a new standard for graphics under Linux. [Source: directfb.org] DirectFB Quick Test Select DirectFB in Package List on LTIB1011: [x] DirectFB Select also DirectFB examples: [x] DirectFB examples Build your Linux. Flash your SD card. Launch your Linux image on your board, and then launch a DirectFB example: $ df_dok DirectFB benchmark is launched. Benchmark result on an i.MX 53 EVK:

Q: MX53 u-boot doc to enable the splash screen and went through Re: MX53 u-boot Splash Screen support but I can't seem to get the splash working on the VGA output. A: FSL do not have solution / recommendations for VGA splash screen under U-boot. Only LVDS is supported. Typically, the Uboot bootloader does not interact with any display interface and does not have a splash screen displaying capability. To add this feature to Uboot on i.MX5 platform, the IPU driver should be included into the Uboot code. Looks like we do not have ready to use solution for the LCD. As an example for LCD configuring it makes sense to use LCD settings from Linux driver. Another approach - to use Linux (Penguin) logo (assuming Linux is booted quickly after U-boot) - at least, Linux supports more display drivers and its logo using is specified. follow up question is since the Tux the penguin logo is only 80x80 is it possible to make a larger image for the Linux start up logo? yes, you should configure kernel for the new image on make menuconfig That doesn’t help this H/W guy, but I think this may - https://community.freescale.com/thread/304300 look for “#To change the splash screen of linux kernel (small penguine on top left corner)..“

Gstreamer Please, select the gstreamer package in [LTIB] under Package List. Choose the package that you will need. For a complete installation, select all: gstreamer gstreamer-plugins-base gstreamer-plugins-good gstreamer-plugins-bad gstreamer-plugins-bad gstreamer-plugins-ugly What can be done With Gstreamer, it's possible to: i.MX27 ADS Board Video GST Play i.MX27 ADS Board Video GST Encode i.MX27 ADS Board Video GST Video Streaming

Overview Resources Download Ubuntu 12.04.01 Download i.MX28EVK BSP and Documents Ubuntu Host Setup Host Package Update Ubuntu Configuration PDF Sudo Priviledges Default Shell CCACHE Directory Layout Extract SDK and Documents Install BSP Sources Ubuntu Software Packages for LTIB Patching LTIB Create SD Card Using Ubuntu Host Media Booting Selection Cable Connections Overview Freescale's i.M28EVK development kit provides a platform for running software and evaluating features of the i.MX28 processor. This document provides the details for running the Linux Board Support Package (BSP) on the Ubuntu 12.04 64-bit Precise Pangolin Host on an Intel/AMD architecture computer. The 32-bit host is not covered in this document and does have different configuration steps than described here. An Ubuntu Linux host is used to cross-compile the BSP creating ARM images. The BSP provides a build system named Linux Target Image Builder, (LTIB), the GNU tool suite for compiling and debugging, U-Boot boot loader, Linux kernel, and a root file system. Resources i.M28EVK- i.MX28 Evaluation Kit Web Page MCIMX28EVKJ Product Summary Page- i.MX28 Download Collateral L2.6.36_MX28_SDK_10.12_Source- BSP Source Download Linux documentation - i.MX28EVK Documentation Ubuntu 12.04.1 LTS (Precise Pangolin)- Ubuntu 12.04 Release Download Ubuntu 12.04.01 A dedicated computer running Ubuntu or a Virtual Machine, (VMware or VirtualBox), can be used for running the Host Ubuntu software. The Ubuntu image is available for downloaded from the Ubuntu site: Ubuntu 12.04.1 LTS (Precise Pangolin). This Ubuntu host ISO was used with the md5 checksum: ubuntu-12.04.1-desktop-amd64.iso 06472ddf11382c8da1f32e9487435c3d One way to acquire the ISO is to use zsync to download: zsync http://releases.ubuntu.com/12.04/ubuntu-12.04.1-desktop-amd64.iso.zsync Once downloaded, installing the ISO is user preference - either a dedicated Linux PC or in a Virtual Machine. Download i.MX28EVK BSP and Documents The BSP download is from this site L2.6.36_MX28_SDK_10.12_Source and the documents from Linux documentation that requires a free registration to specify login credentials, 436e0b8e1c7976c657d530a45f9dbd0c L2.6.35_10.12.01_SDK_source_bundle.tar.gz de0274320a17c1e989d1ef5c088973e2 L2.6.35_10.12.01_SDK_docs.tar.gz Ubuntu Host Setup Ubuntu login credentials of User: user Password: user are used for this documents. Host Package Update Once logged in to the Ubuntu host, the existing packages are brought up to date to the latest version before installing the BSP. The Ubuntu package manager used is apt-get. $ sudo apt-get update $ sudo apt-get upgrade 01. Check all installed packages for new revisions 02. all newer packages found are installed. Addtional packages are required for the ltib build system. Ubuntu Configuration PDF evince is the default pdf reader, another option is zathura. $ sudo apt-get install zathura Sudo Priviledges LTIB requires super user priviledges for some operations. To enable a visudo entry is added to the sudo'ers file. For more information run 'man visudo'. $ sudo visudo The first word, user, is the login account 'user' This can be changed to whatever login you used, or if you have groups configured you can provide a group that developers are in - refer to the man page for sudo for details. Add this line: user ALL =NOPASSWD: /usr/bin/rpm/ /opt/freescale/ltib/usr/bin/rpm Default Shell Ubuntu uses the default shell 'dash'. This however causes failures on bash scripting which is part of the ltib system. Change the default shell from 'dash' to 'bash' $ sudo update-alternatives --install /bin/sh sh /bin/bash 1 CCACHE ccache provides a fast C/C++ compiler cache which is supported in the ltib system. To configure once the ccache package has been installed: $ sudo apt-get install ccache $ ccache -M 50M $ ccache -c 02. Set the cache limit to 50 Meg 03. Clear the cache folder Directory Layout The following directory structure is used: /home/user/freescale/imx28/ |-- archive |-- L2.6.35_10.12.01_ER_source |-- L2.6.35_10.12.01_SDK_docs |-- L2.6.35_10.12.01_SDK_scripts |-- ltib |-- ubuntu-imx28-ltib-patch The archive directory is where the BSP and documents are stored; command to create the directory: $ mkdir -p ~/freescale/imx28/archive Extract SDK and Documents The following instructions were used to extract the contents of the Software Development Kit: $ cd ~/freescale/imx28/archive $ tar -zxf L2.6.35_10.12.01_SDK_source_bundle.tar.gz -C .. 01. Change into the directory containing the tar ball that is compressed. 02. Extract the contents into the directory above (-C ..) the current directory -z unzip -x extract -f L2.6.35_10.12.01_SDK_source_bundle.tar.gz $ tar -zxf L2.6.35_10.12.01_SDK_docs.tar.gz 01. Extract the contents into the directory above (-C ..) the current directory -z unzip -x extract -f L2.6.35_10.12.01_SDK_docs.tar.gz this file The contents of both tar files are now in the directory /home/user/freescale/imx28. Install BSP Sources After extracting the content from the L2.6.35_10.12.01_SDK_source_bundle.tar.gz the file L2.6.35_10.12.01_SDK.source.tar.gz contains all the sources and the build system. Extract the contents and install. This will create the ltib directory which is the build system. $ tar -zxf L2.6.35_10.12.01_SDK_source.tar.gz $ cd L2.6.35_10.12.01_ER_source $ ./install Read the license information and accept by entering YES. An installation directory is then asked for, providing: .. which is the parent directory. The installation script copies the packages and will inform you that 'Installation complete, your ltib installation has been placed in ../ltib, to complete the installation: cd .../ltib ./ltib HOWEVER before doing this, there are packages and patches that need to be applied to run ltib on Ubuntu 12.04.01. Ubuntu Software Packages for LTIB The following packages are required. The script pkg-setup.sh attached below has these packages which can be downloaded and executed to install. $ sh pkg-setup.sh sudo apt-get -y install gettext libgtk2.0-dev rpm bison m4 libfreetype6-dev sudo apt-get -y install libdbus-glib-1-dev liborbit2-dev intltool sudo apt-get -y install ccache zlib1g zlib1g-dev gcc g++ libtool sudo apt-get -y install uuid-dev liblzo2-dev tcl wget libncurses5-dev sudo apt-get -y install libncursesw5-dev lib32z1 libglib2.0-dev xsltproc sudo apt-get -y install ia32-libs libc6-dev-i386 The file pkg2-setup.sh contains optional packages for development. To install, download and execute: $ sh pkg2-setup.sh Please refer to the document ltib_build_host_setup.pdf for more information on host setup. Patching LTIB The location of files from the glibc-devel and zlib Ubuntu 12.04 packages has changed from 9.0.4 Ubuntu which the original ltib was released against. To update ltib operation the following patches are implemented from the directory ~/freescale/imx28/ltib 1. The file ltib is changed at line 2387 adding the '-v' option to the rpm call OLD: system('rpm --force-debian 2>/dev/null') == 0? NEW: system('rpm -v --force-debian 2>/dev/null') == 0? 2. The file bin/Ltibutils.pm is updated to support glibc-devel and zlib. glibc-devel update: Line 563 add check for /usr/lib32/libm.so 'glibc-devel' => sub {-f 'usr/lib/libm.so' || -f '/usr/lib64/libz.so' || -f '/usr/lib32/libm.so'}, zlibc update: Line 584 add /lib/x86_64-linux-gnu/libz.so* zlib => sub{my @f = (glob('/usr/lib/libz.so*'), glob('/lib/x86_64-linux-gnu/libz.so*'), glob('/lib/libz.so*'), The above patches are also in the attachment 0001-patches-for-12.04-ubuntu.patch. LTIB packages also need adjustments to correctly build on Ubuntu. The tar file below, ubuntu-imx28-ltib-patch.tgz contains all the updates. Download and extract the contents at the same directory level as your ltib source directory. $ tar -zxf ubuntu-imx28-ltib-patch.tgz ├── ltib ├── ubuntu-imx28-ltib-patch └── ubuntu-imx28-ltib-patch.tgz Change directories to ubuntu-imx28-ltib-patch and then run the install-patches.sh script. $ cd ubuntu-imx28-ltib-patch $ ./install-patches.sh The following packages are updated: lkc mtd-utils mux_server sparse Create SD Card Using Ubuntu Host The tar file L2.6.35_10.12.01_SDK_scripts.tar.gz contains scripts for writing the images from the ltib build to a SD card. Extract the content, copy the scripts to the ltib directory, and update the mk_mx28_sd script to work with the updated fdisk command. $ tar -zxf L2.6.35_10.12.01_SDK_scripts.tar.gz $ cd L2.6.35_10.12.01_SDK_scripts $ cp mk_hdr.sh ~/freescale/imx28/ltib $ cp mk_mx28_sd ~/freescale/imx28/ltib $ cd ~/freescale/imx28/ltib Edit mk_mx28_sd script and add the 'u' at line 177 then the o command after. This changes cylinders to sectors. OLD: echo "o n NEW: echo "u o n Once updated to create the SD card which is at /dev/sdb: $ ./mk_mx28_sd /dev/sdb NOTE: if mounted automatically, you need to unmount for the script to work $ sudo umount /dev/sdb* Media Booting Selection The i.MX28EVK has a boot option to execute from the SD Card in Slot 0 which is located on the bottom of the EVK. On the top of the EVK there are switches that are read during the start up process to determine what boot media to use. The SD Card in slot 0 is used for this example which requires the settings: B3/DIP1 B2/DIP2 B1/DIP3 B0/DIP4 1 0 0 1 Refer to the user guide, i.MX28_Linux_BSP_UG.pdf section 3.2.1. Boot Modes for all options. The user guide is found in the Linux documentation bundle documentation. Refer to the next section for a picture showing the boot switch location and the SD Card Slot 0 location. Cable Connections A computer serial port is connected to the i.MX28EVK serial port. The communication setting is 115200 baud, 8 data bits, No parity, and 1 stop bit. There is NO flow control set for this port. This is typically shown as 115200, 8N1. The power supply is connected

This is a simple step by step guide on how to change the Android boot animation which is shown when the system is loading. Requirements - Android L5.1.1_2.1.0 BSP. The basics of the boot animation may also apply to older and upcoming releases but L5.1.1_2.1.0 BSP was used for this document. File names, settings or paths may be changed in older or newer releases. - i.MX6Q Sabre SD Board or any other i.MX board supported by the BSP release, for testing. - 7-Zip. This is a free compression tool and has the necessary settings for preparing the boot animation file. It is important that the boot animation file is in Zip format with no compression, otherwise the file won’t be read and the animation will not be shown. Zip tools integrated on some Operating Systems may not always allow for these configurations. You may download this utility from the link below: http://www.7-zip.org/ - Android adb tool. This tool is part of the Android SDK. You may download the SDK as part of Android Studio or the SDK as Stand Alone on the following link. Only the adb is required to follow up this document. http://developer.android.com/sdk/installing/index.html Understanding the boot animation format. The animations used by Android when booting are actually a series of images in either jpg or png format in a zip file with no compression (storage mode) and a text file (desc.txt) with the specified resolution, framerate and loops to be played by the animation. Each folder containing a part of the animation must contain the images numbered from 000 onwards. This file is always called bootanimation.zip An example of a boot animarion can be found attached to this document. The contents of the desc.txt file on the attached example are as follow: 480 292 30 p 1 0 part0 p 0 0 part1 (please note that there should be an empty line at the end of the document). Line 1: Screen resolution followed by FPS (Frames per Second) of the animation. Lines 3-5: The p serves to describe that the line contains a part of the animation; followed by the number of times the section of the animation will play (with zero being an infinite loop); followed by a delay in frames before moving to the next line. Finally, the folder containing the files of that specific part of the animation (this is why most animations use “part” for the folder name). Line 6: A blank line. This is important as without it the animation may not run as it will consider the description file incomplete. There are some animations available around the web as well as some free tools or apps that allow you to create your own animations. You may find an example animation attached to this document which you may use as reference. It is important that no other files are included on the bootanimation.zip file. This includes the thumbnails created automatically by Windows. Please delete them from your fule before loading it to the board. Please note that the animation may be repeated in a loop if it’s shorter than the actual time it takes for the system to load. However, the animation will play complete regardless of the loading time so very long boot animations may give the appearance of a longer booting time. The location of the boot animation file is given on the bootanimation_main.cpp file, which is located on the following path: <MYANDROID_DIR>/frameworks/base/cmds/bootanimation/bootanimation_main.cpp There are two definitions that give the file location. We’re focusing on the default image for this document (unencrypted). #define SYSTEM_BOOTANIMATION_FILE "/system/media/bootanimation.zip" #define SYSTEM_ENCRYPTED_BOOTANIMATION_FILE "/system/media/bootanimation-encrypted.zip" Note: These definitions may be different from those in third party BSPs. It is common to find BSPs using the "/data/local/” folder as USER_BOOTANIMATION. This is not supported by default on NXP’s BSP. Loading the new boot animation file. - Building a User Debug image Android protects certain folders to avoid tampering, so in order to change the boot animation we will use adb in order to access the file system. However, it is necessary to use a image with root access so we will be using a user debug image. In order to compile as user debug use the following lunch command after following the instructions in the Android User's Guide: $ lunch sabresd_6dq-userdebug After configuring the build for user debug you can then build using make. (This process may take several hours) - Enabling USB Debug mode Your board should be running android and then be connected to the computer using the USB OTG port. In order for adb to work you have to enable USB debugging by opening Settings and scrolling down to the “About” option clicking the "About" option 7 times. - Using adb to load the new boot animation We’ll connect to the SABRE board using the Android SDK for Windows adb tool available at the path below: android-sdk-windows\platform-tools Open a command promt in windows and go to the adb path. Then start the adb server with the following command: $ adb start-server This will initialize the adb daemon. In order to connect to the device permission must be granted. A pop up will appear asking whether to trust or not the computer host. Since we will be changing the system partition we must initialize adb as root: $ adb root This will restart the adb daemon in root mode. You will need to grant access from your device. You may see the list of connected with: $ adb devices If you wish to see the contents of the filesystem you may enter the shell with the following command: $ adb shell However, we will be using the pull/push commands from adb in order to change the bootanimation. If you wish to download the current bootanimation for backup you may do so with the following command: $ adb pull /system/media/bootanimation.zip C:\ This will download the bootanimation.zip file to C: Since the system partition is read only you will need to remount with the adb prior to pushing the replacing boot animarion $ adb remount $ adb root push C:\BootAni\bootanimation.zip /system/media After this you may reboot your board and you should see the new boot animation. Original Attachment has been moved to: bootanimation.zip

Adding Support to USB Host High Speed on i.MX27ADS First, ensure these patches were applied: usbh2_cspi1_ss2.patch usbh2_set_ulpi_xcvr.patch Unselect SPI2: Device Drivers ---> SPI support ---> [ ] CSPI2 Select USB Host2: USB support ---> <M> EHCI HCD (USB 2.0) support [*] Support for Host2 port on Freescale controller

The i.MX31 multimedia applications processors are designed for a broad range of industrial, consumer and automotive applications. Based on an ARM1136JF-S™ core, both the i.MX31 and the i.MX31L processors are engineered to deliver powerful performance while minimizing power consumption. The rich feature set of the i.MX31 processors make them an excellent choice for portable media players, portable navigation devices, medical/industrial monitoring systems, automotive infotainment systems and many general embedded applications. i.MX Family Comparison Product Information on Freescale.com i.MX31 Multimedia Applications Processor Evaluation/Development Boards and Systems IMX31PDK: i.MX31 Product Development Kit Getting Started Getting Started with the i.MX31PDK Board Flashing i.MX31 PDK Board I.MX31 PDK Board using RedBoot Miscellaneous Tutorials Blinking iMX31PDK LEDs using U-Boot How to Test i.MX31 RNGA Hardware? How to Test i.MX31 TvOut on i.MX31PDK How to Use Clock Out on i.MX31 Issues when interfacing Micron's 78nm mDDRs IMX31ADS Getting Started Getting Started with the i.MX31ADS Board Flashing I.MX31 ADS Board Miscellaneous Tutorials Booting Linux from NAND Flash on the i.MX31ADS Compiling Linux kernel from mainline to i.MX31ADS Issues when interfacing Micron's 78nm mDDRs Embedded Software and Tools Android OS for i.MX Applications Processors Partners / 3rd-Party Development Tools Starterkit STKa31 (Technology in Quality) Additional Resources i.MX31 ADS i.MX31 PDK i.MX31 PDK Board Alpha Blending i.MX31 PDK Board DirectFB i.MX31 PDK Board V4L tests i.MX31 PDK Contents i.MX31 PDK Setting Buttons and Jumpers i.MX31 Lite Kit

Computer On Module • Processor Freescale i.MX287, 454 MHz • RAM 128MB DDR2-400 SDRAM • ROM 128MB NAND Flash • Power supply Single 3.1V to 5.5V • Size 40mmX35mm • Temp.-Range -40°C..85°C Key Features • Two 10/100Mbps Ethernet ports with IEEE1588 support • Two High-Speed USB 2.0 ports • One colour LCD controller • Two CAN interfaces • 4 wire Touchscreen interface • Several peripheral interfaces: UART, SD-CARD, I2C, PWM, Serial Audio, SPI • Power management optimized for long battery life • 3.3V I/O OS Support • Windows Embedded CE 6.0 • Linux 2.6.35 Application：Building control, factory automation, printers and security panels, HMI, industrial control media gateways / accessories, portable medical devices, energy-saving Energy Gateway / Meter For more information, please see Attachment We can provide a complete solution

The ARD has 2 LVDS connectors, one on the CPU board and a second one on the main board, the LVDS panel (MCIMX-LVDS1) can be connected to these. To enable two independent displays on the Linux BSP 11.05: 1. On u-boot, use the following on the kernel command line for video: video=mxcdi0fb:RGB666,XGA di0_primary ldb=di0 video=mxcdi1fb:RGB666,XGA ldb=di1 2. After boot use memtool to write to the LDB registers to map each LVDS to a display interface: root@freescale ~$ /unit_tests/memtool -32 0x53fa8008=0x0000020d Writing 32-bit value 0x20D to address 0x53FA8008 3. Unblank framebuffer 1: echo 0 > /sys/class/graphics/fb1/blank On the Freescale Linux BSP 11.09 the LDB register write is not needed: 1. On U-boot, use the following on the kernel command line for video: 'video=mxcdi0fb:RGB666,XGA di0_primary ldb=separate,di=0,di=1,ch0_map=SPWG,ch1_map=SPWG video=mxcdi1fb:RGB666,XGA' 2. Unblank framebuffer 1: echo 0 > /sys/class/graphics/fb1/blank

Related links: i.MX Power Profiling System: Smart Current Sensor and Aggregator Shield i.MX Power Profiling System: Aggregator Shield Details i.MX Power Profiling: Triple-range Smart Current Sensor Examples of boards instrumented with Smart Sensors. (Some close-ups will be added later.) One rail of the i.MX7ULP SOM is instrumented here. The sensor is immobilized with foam double sticky tape on top of the i.MX7ULP (trying to minimize contact to just that so the tape is more easily removed later). Immobilization is necessary in order to prevent ripping the resistor pads off the target board. The series resistor on the board is removed and the smart sensor is wired into place. Note here that the sensor is shorted so that the SOM will operate while the Smart Sensor being unpowered. The Smart Sensors MUST be powered via the Aggregator in order for the target board to operate. Otherwise, the target board will be starved of power and it will not operate unless all of the Smart Sensors connected to it are powered. An unpowered Smart Sensor presents an open circuit between the input and output terminals. Here are nine rails instrumented on the i.MX8QM CQC board. One rail Smart Sensor is in the bottom side, the rest are all on top. There is one double sticky taped to the back of the connectors at the back of the photo (the SCU supply, relatively low current, which can tolerate longer wires/series resistance). The rest are connected with 24 gauge wire, no longer than about half an inch long, to keep the series resistance low. The ground wire (center contact) can be a 30 gauge wire-wrap wire, which was used for all the grounds here. Note that the stiff connection wires allow the sensors to stand up in place, which is very helpful since there is no room to double sticky tape the sensors down. This board was not laid out with instrumentation in mind. Here is an i.MX8QXP CQC board with four rails instrumented. Two of the sensors are on top and two on the the bottom. They are not double sticky taped into place, but they are shielded with heat shrink tubing to prevent any contact with the target board. As above, 24 gauge wires are used for the current in/out lines, 30 gauge wire is used for all the ground contacts. Out of the frame, the four ribbon cables are bundled together to prevent the wires and sensors from moving too much. As above, the heavy wires have been kept as short as possible.

i.MX处理器知识库

i.MX Processors Knowledge Base

讨论

How To debug M4 on IMX6SX

How to setup i.MX6Dual/Quad and i.MX6Solo/DualLite Linux software for PCIe compliance Test?

How to upgrade Linux Kernel and dtb on eMMC without UUU

在i.MX8QXP QM平台（L4.14.98 GA）上的OP-TEE中启用CAAM加速

Errata_ERR006282_Description_IMX_Community.pdf

All Boards DirectFB

New Headphone Jack Patch based on Kernel 3.0.35 for imx6_sabresd board

Q&A: How to make MX53 splash screen working on QSB's VGA?

Jumpstart Cloud-Connected Computer Vision and Machine Learning Designs.pdf

i.MX27 ADS Board Video

Freescale iMX6 processor - Garz & Fricke SANTARO 10.4 boxed PCT/resistiv

Ubuntu 12.04 64-bit Precise Pangolin Host Setup for Building i.MX28 L2.6.35_MX28_SDK_10.12_SOURCE [1]

Changing the Android Boot Animation

i.MX27 ADS Adding USB Host2

i.MX31 Multimedia Applications Processors

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