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Introduction This document guides to load a new software image in a KW41 device through Over The Air Programming bootloader. Also, are explained the details of how to set up the client software to change the storage method of the image. Software Requirements IAR Embedded Workbench IDE or MCUXpresso IDE Download both, SDK FRDM-KW41Z and SDK USB-KW41Z. Hardware Requirements FRDM-KW41Z board OTAP Memory Management During the Update Process The KW41 has a 512KB Program Flash with a flash address range from 0x0000_0000 to 0x0007_FFFF.     The OTAP application splits the flash into two independent parts, the OTAP Bootloader, and the OTAP Client. The OTAP Bootloader verifies if there is a new image available at the OTAP Client to reprogram the device. The OTAP Client software provides the Bluetooth LE custom service needed to communicate the OTAP Client device with the OTAP Server that contains the new image file (The OTAP Server device could be another FRDM-KW41Z connected to a PC with Test Tool or a Smartphone with IoT Toolbox app). Therefore, the OTAP Client device needs to be programmed twice, first with the OTAP Bootloader, then with the Bluetooth LE application supporting OTAP Client. The mechanism created to have two different software coexisting in the same device is storing each one in different memory regions. This functionality is implemented by the linker file. In the KW41 device, the bootloader has reserved a 16 KB slot of memory from 0x0000_0000 to 0x0003_FFFF, thus the left memory is reserved among other things, by the OTAP Client demo. To create a new image file for the client device, the developer needs to specify to the linker file that the code will be built with an offset of 16 KB since the first addresses must be reserved for the OTAP Bootloader. In connection state, the OTAP server sends the image packets (known as chunks) to the OTAP Client device via Bluetooth LE. The OTAP Client device can store these chunks, in first instance, at the external SPI flash or the On-Chip Flash. The destination of the code is selectable in the OTAP Client software. When the connection has finished and all chunks were sent from the OTAP Server to the OTAP Client device, the OTAP Client software writes information, such as the source of the image update (external flash or internal flash) in a portion of memory known as Bootloader Flags and then resets the MCU to execute the OTAP Bootloader code. The OTAP Bootloader reads the Bootloader Flags to get the information needed to program the device and triggers a commando to reprogram the MCU with the new application. Due to the new application was built with an offset of 16 KB, the OTAP Bootloader programs the device starting from the 0x0000_4000 address and the OTAP Client application is overwritten by the new image, therefore, after the device has been reprogrammed through this method, cannot be programmed a second time as same. Finally, the OTAP Bootloader triggers a command to start the execution of the new code automatically.     Preparing the Software to Test the OTAP Client for KW41Z Device Using IAR Embedded Workbench Program the OTAP Bootloader on the FRDM-KW41Z. Program the OTAP Bootloader software from the project included in the SDK FRDM-KW41Z at the following path, or you can simply drag and drop the pre-built binary from the following path.           OTAP Bootloader Project:          <SDK_2.2.0_FRDM-KW41Z_download_path>\boards\frdmkw41z\wireless_examples\framework\bootloader_otap\bm\iar\bootloader_otap_bm.eww            OTAP Bootloader pre-built binary:            <SDK_2.2.0_FRDM-KW41Z_download_path>\tools\wireless\binaries\bootloader_otap_frdmkw41z.bin   Open the OTAP Client project included in the SDK FRDM-KW41Z located in the following path.          <SDK_2.2.0_FRDM-KW41Z_download_path>\boards\frdmkw41z\wireless_examples\bluetooth\otap_client_att\freertos\iar\otap_client_att_freertos.eww   Customize the OTAP Client software to select the storage method. Locate the app_preinclude.h header file inside the source folder at the workspace. To select the External Flash storage method, set the " gEepromType_d " define to " gEepromDevice_AT45DB041E_c "                       To select the Internal Flash storage method, set the  " gEepromType_d " define to " gEepromDevice_InternalFlash_c "   Configure the linker flags. Open the project options window (Alt + F7). In "Linker->Config" window, locate the "Configuration file symbol definitions" pane. To select the External Flash storage method, remove the " gUseInternalStorageLink_d=1 " linker flag To select the Internal Flash storage method, add the " gUseInternalStorageLink_d=1 " linker flag     Load the OTAP Client software on the FRDM-KW41Z board (Ctrl + D). Stop the debug session (Ctrl + Shift + D). The default linker configurations of the project allow the OTAP Client application to be stored with the proper memory offset.   Preparing the Software to Test the OTAP Client for KW41Z Device Using MCUXpresso IDE Program the OTAP Bootloader on the FRDM-KW41Z. Program the OTAP Bootloader software from the project included in the SDK FRDM-KW41Z at the following path, or you can simply drag and drop the pre-built binary from the following path.           OTAP Bootloader Project:          wireless_examples->framework->bootloader_otap->bm            OTAP Bootloader pre-built binary:            <SDK_2.2.0_FRDM-KW41Z_download_path>\tools\wireless\binaries\bootloader_otap_frdmkw41z.bin   Click on "Import SDK examples(s)" option in the "Quickstart Panel" view. Click twice on the frdmkw41z icon.     Open the OTAP Client project included in the SDK FRDM-KW41Z located in the following path. wireless_examples->bluetooth->otap_client_att->freertos     Customize the OTAP Client software to select the storage method. Locate the app_preinclude.h header file inside the source folder at the workspace. To select the External Flash storage method, set the " gEepromType_d " define to " gEepromDevice_AT45DB041E_c "                       To select the Internal Flash storage method, set the  " gEepromType_d " define to " gEepromDevice_InternalFlash_c "   Configure the linker file. To select the External Flash storage method, are not required any changes in the project from this point. You can skip this step. To select the Internal Flash storage method, search the linker file located in the SDK USB-KW41Z at the following path and replace instead of the default linker file at the source folder in the OTAP Client project. You can copy (Ctrl + C) the linker file from SDK USB-KW41Z  and paste (Ctrl + V) on the workspace directly. A warning message will be displayed, select "Overwrite".           Linker file at the SDK USB-KW41Z:        <SDK_2.2.0_USB-KW41Z_download_path>\boards\usbkw41z_kw41z\wireless_exa mples\bluetooth\otap_client_att\freertos\MKW41Z512xxx4_connectivity.ld     Save the changes in the project. Select "Debug" in the "Quickstart Panel". Once the project is already loaded on the device, stop the debug session.   Creating an S-Record Image File for FRDM-KW41Z OTAP Client in IAR Embedded Workbench Open the connectivity project that you want to program using the OTAP Bootloader from your SDK FRDM-KW41Z. This example will make use of the glucose sensor project, this is located at the following path. <SDK_2.2.0_FRDM-KW41Z_download_path>\boards\frdmkw41z\wireless_examples\bluetooth\glucose_sensor\freertos\iar\glucose_sensor_freertos.eww   Open the project options window (Alt+F7). In Linker->Config window, add the following linker flag in the “Configuration file symbol definitions” textbox.          gUseBootloaderLink_d=1     Go to the “Output Converter” window. Deselect the “Override default" checkbox, expand the “Output format” combo box and select Motorola S-records format. Click the OK button.     Rebuild the project. Search the S-Record file (.srec) in the following path. <SDK_2.2.0_FRDM-KW41Z_download_path>\boards\frdmkw41z\wireless_examples\bluetooth\glucose_sensor\freertos\iar\debug   Creating an S-Record Image File for FRDM-KW41Z OTAP Client in MCUXpresso IDE Open the connectivity project that you want to program using the OTAP Bootloader from MCUXpresso IDE. This example will make use of the glucose sensor project, this is located at the following path.         wireless_examples->bluetooth->glucose_sensor->freertos   Search the linker file located in the  SDK FRDM-KW41Z   at the path below and replace instead of the default linker file at the source folder in the Glucose Sensor project. You can copy (Ctrl + C) the linker file from   SDK FRDM-KW41Z  and paste (Ctrl + V) on the workspace directly. A warning message will be displayed, select "Overwrite".          Linker file at the SDK FRDM-KW41Z:          <SDK_2.2.0_FRDM-KW41Z_download_path>\boards\ frdmkw41z \wireless_exa mples\bluetooth\otap_client_att\freertos\MKW41Z512xxx4_connectivity.ld     Open the new "MKW41Z512xxx4_connectivity.ld" linker file. Locate the section placement of the figure below and remove the "FILL" and the "BYTE" statements.         Build the project. Deploy the “Binaries” icon in the workspace. Click the right mouse button on the “.axf” file. Select the “Binary Utilities/Create S-Record” option. The S-Record file will be saved at “Debug” folder in the workspace with “.s19” extension.     Testing OTAP Client Demo Using IoT Toolbox App Save the S-Record file created with the steps in the last section in your smartphone at a known location. Open the IoT Toolbox App and select OTAP demo. Press “SCAN” to start scanning for a suitable advertiser. Press the “SW4” button on the FRDM-KW41Z board to start advertising. Create a connection with the found device. Press “Open” and search the S-Record file. Press “Upload” to start the transfer. Once the transfer is complete, wait a few seconds until the bootloader has finished programming the new image. The new application will start automatically. 
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Hello everyone, Over The Air Programming (OTAP) NXP's custom Bluetooth LE service provides the developer a solution to upgrade the software that the MCU contains. It removes the need for cables and a physical link between the OTAP client (the device that is reprogrammed) and the OTAP server (the device that contains the software update). This post explains how to run the OTAP Client Software that comes within the FRDM-KW36 package: Reprogramming a KW36 device using the OTAP Client Software. As it is mentioned in the last post, the OTAP Client can reprogram the KW36 while it is running, with new software using Bluetooth LE. However, this implementation for most of the applications is not enough since once you have reprogrammed the new image, the KW36 can not be reprogramed a second time using this method. For these applications that require to be updated many times using Bluetooth LE during run-time, we have created the following application note, that comes with a functional example of how to implement the OTAP Client software, taking advantage of this service. You can download the software clicking on the link in blue and the documentation is in the link in green. Please visit the following link: DOCUMENTS and Application Notes for KW36 In the "DOCUMENTS" section, you can found more information of the KW36. In the "Application Note" section, you can found more software and documentation of interesting topics like this.        Best Regards.
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Introduction The FRDM-KW36 includes an RSIM (Radio System Integration Module) module with an external 32 MHz crystal oscillator. This clock source reference is mainly intended to supply the Bluetooth LE Radio peripheral, but it can be used as the main clock source of the MCU as well.  This oscillator includes a set of programmable capacitors to support crystals with different load capacitance needs. Changing the value of these capacitors can modify the frequency the oscillator provides, that way, the central frequency can be tuned to meet the wireless protocol standards.  This configurable capacitance range is from C1: 5.7pF - C2: 7.1pF to C1: 22.6pF - C2: 28.2pF and it is configured through the  BB_XTAL_TRIM field at the ANA_TRIM.  The KW36 comes preprogrammed with a default load capacitance value. However, since there is variance in devices due to tolerances and parasite effects, the correct load capacitance should be checked by verifying that the optimal central frequency is attained.  You will need a spectrum analyzer to measure the central frequency. To find the most accurate value for the load capacitance, it is recommended to use the Connectivity Test demo application. Adjusting Frequency Example Program the KW36 Connectivity Test software on the device. This example can be found in wireless_examples -> genfsk -> conn_test folder from your SDK package. Baremetal and FreeRTOS versions are available. In case that FRDM-KW36 board is being used to perform the test, you should move the 10pF capacitor populated in C55 to C57, to direct the RF signal on the SMA connector. Connect the board to a serial terminal software. When you start the application, you will be greeted by the NXP logo screen:  Press the enter key to start the test. Then press "1" to select "Continuous tests": Finally, select "6" to start a continuous unmodulated RF test. At this point, you should be able to measure the signal in the spectrum analyzer. You can change the RF channel from 0 to 127 ( "q" Ch+ and "w" Ch- keys), which represents the bandwidth from 2.360GHz to 2.487GHz, stepping of 1MHz between two consecutive channels. To demonstrate the trimming procedure, this document will make use of channel 42 (2.402GHz) which corresponds to the Bluetooth LE channel 37. In this case, with the default capacitance value, our oscillator is not exactly placed at the center of the 2.402GHz, instead, it is slightly deflected to 2.40200155 GHz, as depicted in the following figure: The capacitance can be adjusted with the "d" XtalTrim+ and "f" XtalTrim- keys. Increasing the capacitance bank means a lower frequency. In our case, we need to increase the capacitance to decrease the frequency. The nearest frequency of 2.402 GHz was 2.40199940 GHz  Once the appropriate XTAL trim value has been found, it can be programmed as default in any Bluetooth LE example, changing the mXtalTrimDefault constant located in the board.c file: static const uint8_t mXtalTrimDefault‍ = 0x36;‍‍‍
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Introduction In some applications, is it necessary to keep updated the software running in many MCU's that take part in the system, fortunately, Over The Air Programming, it's a custom Bluetooth LE service developed to send "over the air" software updates for the KW MCU series. FRDM-KW36 SDK already provides the "otap_client" software, that can be used together with the "otap_bootloader" such as it is described in the following community post:  Reprogramming a KW36 device using the OTAP Client Software  to reprogram the KW36. This example can be modified to store code for another MCU and later send the software update to this device as depicted in the figure below. This post guides you on modifying the OTAP client software to support software updates for other MCU's. Preparing the OTAP client software The starting point of the following modifications is supposing that there is no need to perform over the air updates for the KW36 MCU, so the use of the "otap_bootloader" is obsolete and will be removed in this example. In other words, KW36 will be programmed only with the "otap_client" code. Open the MCUXpresso settings window (Project->Properties->"C/C++ Build->MCU settings") and configure the following fields. Save the changes. For external storage: For internal storage: Locate the "app_preinclude.h" file, and set the storage method, as follows: For external storage: #define gEepromType_d       gEepromDevice_AT45DB041E_c For internal storage: #define gEepromType_d        gEepromDevice_InternalFlash_c Locate the "main_text_section.ldt" linker script into the "linkscripts" folder, and delete it from the project.  Search in the project for   "OTA_SetNewImageFlag();" and "ResetMCU();"  functions in the "otap_client.c" file (source->common->otap_client->otap_client.c) and delete or comment. (For reference, there are 4 in total). Locate the following code in "OtaSupport.h" (framework->OtaSupport->Interface) and delete or comment. extern uint16_t gBootFlagsSectorBitNo;‍‍‍‍‍‍ void OTA_SetNewImageFlag(void);‍‍‍‍‍‍‍ Locate the following code in "OtaSupport.c" (framework->OtaSupport->Source) and delete or comment. extern uint32_t __BootFlags_Start__[]; #define gBootImageFlagsAddress_c ((uint32_t)__BootFlags_Start__)‍‍‍‍‍‍‍‍‍‍‍‍ #if !gEnableOTAServer_d || (gEnableOTAServer_d && gUpgradeImageOnCurrentDevice_d) /*! Variables used by the Bootloader */ #if defined(__IAR_SYSTEMS_ICC__) #pragma location = "BootloaderFlags" const bootInfo_t gBootFlags = #elif defined(__GNUC__) const bootInfo_t gBootFlags __attribute__ ((section(".BootloaderFlags"))) = #elif defined(__CC_ARM) volatile const bootInfo_t gBootFlags __attribute__ ((section(".BootloaderFlags"))) = #else #error "Compiler unknown!" #endif { {gBootFlagUnprogrammed_c}, {gBootValueForTRUE_c}, {0x00, 0x02}, {gBootFlagUnprogrammed_c}, #if defined(CPU_K32W032S1M2VPJ_cm4) && (CPU_K32W032S1M2VPJ_cm4 == 1) {PLACEHOLDER_SBKEK}, {BOOT_MAGIC_WORD} #endif }; #endif /* !gEnableOTAServer_d || (gEnableOTAServer_d && gUpgradeImageOnCurrentDevice_d) */‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ uint16_t gBootFlagsSectorBitNo; gBootFlagsSectorBitNo = gBootImageFlagsAddress_c/(uint32_t)((uint8_t*)FSL_FEATURE_FLASH_PFLASH_BLOCK_SECTOR_SIZE);‍‍‍‍ gBootFlagsSectorBitNo = gBootImageFlagsAddress_c/(uint32_t)((uint8_t*)FSL_FEATURE_FLASH_PAGE_SIZE_BYTES);‍‍‍‍ void OTA_SetNewImageFlag(void) { #if (gEepromType_d != gEepromDevice_None_c) && (!gEnableOTAServer_d || (gEnableOTAServer_d && gUpgradeImageOnCurrentDevice_d)) /* OTA image successfully written into the non-volatile storage. Set the boot flag to trigger the Bootloader at the next CPU Reset. */ union{ uint32_t value; uint8_t aValue[FSL_FEATURE_FLASH_PFLASH_BLOCK_WRITE_UNIT_SIZE]; }bootFlag; #if defined(CPU_K32W032S1M2VPJ_cm4) && (CPU_K32W032S1M2VPJ_cm4 == 1) uint8_t defaultSBKEK[SBKEK_SIZE] = {DEFAULT_DEMO_SBKEK}; #endif uint32_t status; if( mNewImageReady ) { NV_Init(); bootFlag.value = gBootValueForTRUE_c; status = NV_FlashProgramUnaligned((uint32_t)&gBootFlags.newBootImageAvailable, sizeof(bootFlag), bootFlag.aValue); if( (status == kStatus_FLASH_Success) && FLib_MemCmpToVal(gBootFlags.internalStorageAddr, 0xFF, sizeof(gBootFlags.internalStorageAddr)) ) { bootFlag.value = gEepromParams_StartOffset_c + gBootData_ImageLength_Offset_c; status = NV_FlashProgramUnaligned((uint32_t)&gBootFlags.internalStorageAddr, sizeof(bootFlag), bootFlag.aValue); } #if defined(CPU_K32W032S1M2VPJ_cm4) && (CPU_K32W032S1M2VPJ_cm4 == 1) if( status == kStatus_FLASH_Success ) { /* Write the default SBKEK for secured OTA */ status = NV_FlashProgramUnaligned((uint32_t)&gBootFlags.sbkek, SBKEK_SIZE, defaultSBKEK); } #endif if( status == kStatus_FLASH_Success ) { mNewImageReady = FALSE; } } #endif }‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍   At this point, the FRDM-KW36 can receive and store any image for any MCU and can request a further software update from the OTAP server device.    Adding API's to reprogram the "MCU X" on OTAP client software Once the software update has been downloaded from the OTAP Server into the OTAP Client, the developer should request the software update from the OTAP Client to the "MCU X" through a serial protocol such as UART, SPI, CAN, etc. You should develop the API's and the protocol according to the requirements for your system to send the software update to the "MCU X" (as well as the bootloader for the MCU X). The handling your protocol can be integrated into the OTAP client code replacing "ResetMCU()" (The same code removed in step 4) in the code by "APISendSoftwareUpdateToMCUX()" for instance, since at this point the image was successfully sent over the air and stored in the memory of the KW36. 
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Introduction The FRDM-KW36 includes an RTC module with a 32 kHz crystal oscillator. This module generates a 32 kHz clock source for the MCU whilst running on very low power mode. This oscillator includes a set of programmable capacitors used as the C LOAD . Changing the value of these capacitors can modify the frequency the oscillator provides. This configurable capacitance ranges from 0 pF (capacitor bank disabled) to 30  pF in steps of 2 pF . These values are obtained by combining the enabled capacitors. The values available are 2  pF , 4  pF , 8  pF , and 16  pF .   Any combination of these four can be done.  It is recommended that these internal capacitors are disabled if the external capacitors are available (clearing SC2P, SC4P, SCS8, and SC16 bits in RTC Control Register SFR). To adjust the frequency provided by the oscillator, you must first be able to measure the frequency. Using a frequency counter would be ideal, as it provides a more precise measurement than an oscilloscope. You will also need to output the oscillator frequency.  To output the oscillator frequency, u sing any of the Bluetooth demo applications as an example, you should do the following: Adjusting Frequency Example This example will make use of the Heart Rate Sensor demo (freertos version) from the Connectivity Software Stack and assumes that the developer has the knowledge of import or open projects from the SDK to IDE. Open or clone the Heart Rate Sensor project from your SDK. Find the board.c and board.h files in the board folder at the workspace.                                                                                Declare a void function on the board.h file as shown below. This function will be in order to mux the RTC clock out to the PTB3 and be able to measure the frequency.  /* Function to mux PTB3 to RTC_CLKOUT */ void BOARD_EnableRtcClkOut (void);‍‍ Develop the BOARD_EnableRtcClkOut function inside the board.c file as below. void BOARD_EnableRtcClkOut(void) { /* Enable PORTB clock gating */ CLOCK_EnableClock(kCLOCK_PortB); /* Mux the RTC_CLKOUT to PTB3 */ PORT_SetPinMux(PORTB, 3u, kPORT_MuxAlt7); /* Select the 32kHz reference for RTC_CLKOUT signal */ SIM->SOPT1 |= SIM_SOPT1_OSC32KOUT(1); } Call the BOARD_EnableRtcClkOut function in hardware_init function just after BOARD_BootClockRUN (board.c file). Find clock_config.c file in the board folder at the workspace. Add the following defines at the top of the file. #define RTC_OSC_CAP_LOAD_0 0x0U /*!< RTC oscillator, capacitance 0pF */ #define RTC_OSC_CAP_LOAD_2 0x2000U /*!< RTC oscillator, capacitance 2pF */ #define RTC_OSC_CAP_LOAD_4 0x1000U /*!< RTC oscillator, capacitance 4pF */ #define RTC_OSC_CAP_LOAD_6 0x3000U /*!< RTC oscillator, capacitance 6pF */ #define RTC_OSC_CAP_LOAD_8 0x800U /*!< RTC oscillator, capacitance 8pF */ #define RTC_OSC_CAP_LOAD_10 0x2800U /*!< RTC oscillator, capacitance 10pF */ #define RTC_OSC_CAP_LOAD_12 0x1800U /*!< RTC oscillator, capacitance 12pF */ #define RTC_OSC_CAP_LOAD_14 0x3800U /*!< RTC oscillator, capacitance 14pF */ #define RTC_OSC_CAP_LOAD_16 0x400U /*!< RTC oscillator, capacitance 16pF */ #define RTC_OSC_CAP_LOAD_18 0x2400U /*!< RTC oscillator, capacitance 18pF */ #define RTC_OSC_CAP_LOAD_20 0x1400U /*!< RTC oscillator, capacitance 20pF */ #define RTC_OSC_CAP_LOAD_22 0x3400U /*!< RTC oscillator, capacitance 22pF */ #define RTC_OSC_CAP_LOAD_24 0xC00U /*!< RTC oscillator, capacitance 24pF */ #define RTC_OSC_CAP_LOAD_26 0x2C00U /*!< RTC oscillator, capacitance 26pF */ #define RTC_OSC_CAP_LOAD_28 0x1C00U /*!< RTC oscillator, capacitance 28pF */ #define RTC_OSC_CAP_LOAD_30 0x3C00U /*!< RTC oscillator, capacitance 30pF */ Search the CLOCK_CONFIG_EnableRtcOsc call to a function inside the BOARD_BootClockRUN function (also in the clock_config.c file), and edit the argument by any of the defines above. Finally, disable the low power options and led support in the "preinclude.h" file located in the source folder of the project: #define cPWR_UsePowerDownMode 0 #define gLEDSupported_d 0 At this point, you can measure in PTB3 and play with the frequency adjust using your frequency counter. Each time that the board is programmed, you need to perform a POR to get the correct measure. The following table was obtained from an FRDM-KW36 board rev B and it can be used as a reference to adjust the frequency.  Please note that the capacitance is not only composed of the enabled internal capacitance, but also the parasitic capacitances found in the package, bond wires, bond pad, and the PCB traces. So, while the reference measurements given below should be close to the actual value, you should also make measurements with your board, to ensure that the frequency is trimmed specifically to your board and layout.   Enabled Capacitors C LOAD Capacitance Definition Frequency - 0pF RTC_OSC_CAP_LOAD_0 (bank disabled) 32772.980Hz SC2P 2pF RTC_OSC_CAP_LOAD_2 32771.330Hz SC4P 4pF RTC_OSC_CAP_LOAD_4 32770.050Hz SC2P, SC4P 6pF RTC_OSC_CAP_LOAD_6 32769.122Hz SC8P 8pF RTC_OSC_CAP_LOAD_8 32768.289Hz SC2P, SC8P 10pF RTC_OSC_CAP_LOAD_10 32767.701Hz SC4P, SC8P 12pF RTC_OSC_CAP_LOAD_12 32767.182Hz SC2P, SC4P, SC8P 14pF RTC_OSC_CAP_LOAD_14 32766.766Hz SC16P 16pF RTC_OSC_CAP_LOAD_16 32766.338Hz SC2P, SC16P 18pF RTC_OSC_CAP_LOAD_18 32766.038Hz SC4P, SC16P 20pF RTC_OSC_CAP_LOAD_20 32765.762Hz SC2P, SC4P, SC16P 22pF RTC_OSC_CAP_LOAD_22 32765.532Hz SC8P, SC16P 24pF RTC_OSC_CAP_LOAD_24 32765.297Hz SC2P, SC8P, SC16P 26pF RTC_OSC_CAP_LOAD_26 32765.117Hz SC4P, SC8P, SC16P 28pF RTC_OSC_CAP_LOAD_28 32764.940Hz SC2P, SC4P, SC8P, SC16P 30pF RTC_OSC_CAP_LOAD_30 32764.764Hz
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Bluetooth Low Energy offers the ability to broadcast data in format of non-connectable advertising packets while not being in a connection. This GAP Advertisement is widely known as a beacon and there are currently different beacon formats on the market.   This guide will help you to create your own beacon scanner to detect from which type of device is the beacon received from. This guide it’s based on the frdmkw41z_wireless_examples_bluetooth_temperature_collector_freertos  demo in MCUXpresso  The first thing we will do it’s to disable the low power to make the development easier in the app_preinclude.h /* Enable/Disable PowerDown functionality in PwrLib */ #define cPWR_UsePowerDownMode 0‍‍‍‍ ‍ ‍   The following changes will be all performed in the temperature_collector.c file We will disable the timer so it keeps scanning the packets received   /* Start advertising timer TMR_StartLowPowerTimer(mAppTimerId, gTmrLowPowerSecondTimer_c, TmrSeconds(gScanningTime_c), ScanningTimeoutTimerCallback, NULL); */ ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍   Then we will define some of the data we want to use as a reference. static uint8_t NXPAd [ 3 ] = { /* Company Identifier*/ mAdvCompanyId , /* Beacon Identifier */ 0xBC } ; ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍   static uint8_t iBeaconAd [ 2 ] = { 0x4C , 0x00 } ; ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ ‍ ‍ ‍ ‍ ‍ static uint8_t EddyStoneUIDAd2 [ 3 ] = { /* ID */ 0xAA , 0xFE , /* Frame Type */ 0x00 } ; ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍     static const uint8_t EddyStoneURLAd2 [ 3 ] = { /* ID */ 0xAA , 0xFE , /* Frame Type */ 0x10 } ; ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍     static const uint8_t EddyStoneTLMAd2 [ 3 ] = { /* ID */ 0xAA , 0xFE , /* Frame Type */ 0x20 } ; ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍   Once we have those definitions of the beacon structure of each of the types wanted we will change the function static bool_t CheckScanEvent(gapScannedDevice_t* pData) static bool_t CheckScanEvent ( gapScannedDevice_t * pData ) { uint8_t index = 0 ; bool_t foundMatch = FALSE ; bool_t EddyfoundMatch = FALSE ; while ( index < pData -> dataLength ) { gapAdStructure_t adElement ; adElement . length = pData -> data [ index ] ; adElement . adType = ( gapAdType_t ) pData -> data [ index + 1 ] ; adElement . aData = & pData -> data [ index + 2 ] ; /*DESIRED BEACON SCANNER PARSER CODE */ /* Move on to the next AD elemnt type */ index + = adElement . length + sizeof ( uint8_t ) ; } if ( foundMatch ) { SHELL_NEWLINE ( ) ; shell_write ( "\r\Address : " ) ; shell_writeHex ( pData -> aAddress , 6 ) ; } return foundMatch ; } ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍   As you can see, there is a comment in the function that mentions the need to add the scanner parser code, depending on the beacon you want to see  will be the code to use there  NXP if ( FLib_MemCmp ( NXPAD , ( adElement . aData ) , 2 ) ) { shell_write ( "\r\nFound NXP device!" ) ; SHELL_NEWLINE ( ) ; shell_write ( "\r\nData Received: " ) ; shell_writeHex ( adElement . aData , adElement . length ) ; foundMatch = TRUE ; } ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍   iBeacon if ( FLib_MemCmp ( iBeaconAd , ( adElement . aData ) , 2 ) ) { shell_write ( "\r\nFound iBeacon device!" ) ; SHELL_NEWLINE ( ) ; shell_write ( "\r\nData Received: " ) ; shell_writeHex ( adElement . aData , adElement . length ) ; foundMatch = TRUE ; } ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ Eddystone if ( FLib_MemCmp ( EddyStoneUIDAd1 , ( adElement . aData ) , 2 ) ) { shell_write ( "\r\nFound EddyStone device!" ) ; if ( ! EddyfoundMatch ) { EddyfoundMatch = TRUE ; } else { if ( TRUE == EddyfoundMatch && FLib_MemCmp ( EddyStoneUIDAd2 , ( adElement . aData ) , 3 ) ) { SHELL_NEWLINE ( ) ; shell_write ( "\r\n[UID type] Data Received: " ) ; shell_writeHex ( adElement . aData , adElement . length ) ; foundMatch = TRUE ; EddyfoundMatch = FALSE ; } else if ( TRUE == EddyfoundMatch && FLib_MemCmp ( EddyStoneURLAd2 , ( adElement . aData ) , 3 ) ) { SHELL_NEWLINE ( ) ; shell_write ( "\r\n[URL type] Data Received: " ) ; hell_writeHex ( adElement . aData , adElement . length ) ; foundMatch = TRUE ; EddyfoundMatch = FALSE ; } else if ( TRUE == EddyfoundMatch && FLib_MemCmp ( EddyStoneTLMAd2 , ( adElement . aData ) , 3 ) ) { SHELL_NEWLINE ( ) ; shell_write ( "\r\n[TLM type] Data Received: " ) ; shell_writeHex ( adElement . aData , adElement . length ) ; foundMatch = TRUE ; EddyfoundMatch = FALSE ; } else { EddyfoundMatch = TRUE ; } } } ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍
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The FRDM-KW36 comes with the OpenSDA circuit which allows users to program and debug the evaluation board. There are different solutions to support such OpenSDA circuits: 1. The J-Link (SEGGER) firmware.  2. The CMSIS-DAP (mbed) firmware. The FRDM-KW36 comes pre-programmed with the CMSIS-DAP firmware. However, if you want to update the firmware version, you need to perform the next steps.  Press and hold the Reset button (SW1 push button in the board).  Unplug and plug the FRDM-KW36 again to the PC.  The board will be enumerated as "DAPLINKBOOT" device. Drag and drop the binary file to update the OpenSDA firmware.  If the J-Link version is programmed, the board will be enumerated as "FRDM-KW36J". On the other hand, if the CMSIS-DAP version is programmed, the board will be enumerated as "FRDM-KW36". The binary for the J-link version can be downloaded from the next link: SEGGER - The Embedded Experts - Downloads - J-Link / J-Trace  The binary for the CMSIS-DAP version can be found in the next link: OpenSDA Serial and Debug Adapter|NXP    Hope this helps... 
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I got a question related to best practices to configure a GPIO if the pin is not used. To make it short, the recommendation is to leave the GPIO floating on the PCB and leave the GPIO in its "Default" state as shown in the Signal Multiplexing table in the Reference Manual. The Default state is either “Disabled” or an analog function.   Some Kinetis devices have analog only pins (PGAx/ADCx) while most have GPIO pins with analog functions (PTx/ADCx) or digital GPIO pins   Unused pins, whether analog only or GPIO, should be left floating. Analog only pins do not have input buffers that will cause shoot-through currents when the input floats. GPIO pins with analog functions default to analog functions, which disables the digital input buffer – no shoot-through current.   The digital GPIO pins default to "Disabled", which disables the input buffers - no shoot-through currents with floating inputs.   Finally, unused pins shall not be tied to VDD or VSS. Hence, when designing your board and there are some unused pins, leave them floating on the PCB and then make sure that the software leaves the GPIO in its Default state in the MUX register. 
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This document describes the Persistent Data Manager (PDM) module which handles the storage of stack context data and application data in Non-Volatile Memory (NVM). For the KW41Z devices, this memory is internal Flash and this document will therefore refer to Flash. Tip: In this document, a cold start refers to either a first-time start or a re-start without memory (RAM) held. A warm start refers to a re-start with memory held (for example following sleep with memory held). 1.    Overview If the data needed for the operation of a network node is stored only in on-chip RAM, this data is maintained in memory only while the node is powered and will be lost during an interruption to the power supply (e.g. power failure or battery replacement). This data includes context data for the network stack and application data. In order for the node to recover from a power interruption with continuity of service, provision must be made for storing essential operational data in Non-Volatile Memory (NVM), such as Flash. This data can then be recovered during a re-boot following power loss, allowing the node to resume its role in the network. The storage and recovery of operational data in KW41Z Flash can be handled using the Persistent Data Manager (PDM) module, as described in the rest of this document, which covers the following topics: Initializing the PDM module - see Section 2 Managing data in Flash - see Section 3 PDM features like record searching by record ID – see Section 4 The PDM can be used with ZigBee PRO and IEEE802.15.4 wireless networking protocols. 2.    Initializing the PDM and Building a File System Using the Kinetis NVM framework requires that the user must register the necessary data sets for NVM writing. This is done by calling function NVM_RegisterDataSet(). This function registers the given data set to be written in the NVM_TABLE section from Flash. The PDM module must be initialized by the application following a cold or warm start, irrespective of the PDM functionality used (e.g. context data storage or counter implementation). PDM initialization is performed using the function PDM_eInitialise(). This function requires the following information to be specified: The number of Flash sectors to be used by PDM (a zero value means use all segments) Once the PDM_eInitialise() function has been called, the PDM module builds a file system in RAM containing information about the sectors that it manages in Flash. The PDM reads the header data from each Flash sector and builds the file system. Application records are grouped and initialized in function InitAplRecords(), while network stack records are grouped and initialized in function InitNwkRecords(). For ZigBee PRO, the PDM is used in its most general form, as described above. 3.    Managing Data in Flash This section describes use of the PDM module to persist data in Flash in order to provide continuity of service when the KW41Z device resumes operation after a cold start or a warm start without memory held. Data is stored in Flash in terms of ‘records’. A record occupies at least one Flash sector but may be larger than a sector and occupy multiple sectors. Any number of records of different lengths can be created, provided that they do not exceed the Flash capacity. The records are created automatically for stack context data and by the application (as indicated in Section 3.1) for application data. Each record is identified by a unique 16-bit value which is assigned when the record is created - for application data, this identifier is user-defined. The stack context data which is stored in Flash includes the following: Application layer data: AIB members, such as the EPID and ZDO state Group Address table Binding table Application key-pair descriptor Trust Centre device table Network layer data: NIB members, such as PAN ID and radio channel Neighbor table Network keys Address Map table On performing a KW41Z cold start or warm start without RAM held, the PDM must be initialized in the application as described in Section 2. If this is the first ever cold start, there will be no stack context data or application data preserved in the Flash. If it is a cold or warm start following previous use (such as after a reset), there should be stack context data and application data preserved in the Flash. On start-up, the PDM builds a file system in RAM and scans the Flash for valid data. If any data is found, it is incorporated in the file system. Saving and recovering application data in Flash are described in the subsections below. 3.1   Saving Data to Flash       Application data and stack context data are saved from RAM to Flash as described below.       Note: During a data save, if the Flash needs to be defragmented and purged, this will be performed automatically resulting in all records being re-saved.     Application data           You should save application data to Flash when important changes have been made to the data in RAM. Application data in RAM can be saved to an individual record           in Flash using the function PDM_eSaveRecordData(). A buffer of data in RAM is saved to a single record in Flash (a record may span multiple Flash sectors).          The records are created when calling PDM_eInitialise(). These records are traced by a unique 16-bit identifier assigned by the application - this identifier is subsequently          used to reference the record. The value used must not clash with those used by the NXP libraries - the ZigBee PRO stack libraries use values above 0x8000.          Subsequently, in performing a re-save to the same record (specified by its 16-bit identifier), the original Flash sectors associated with the record will be overwritten but          only the sector(s) containing data changes will be altered (if no data has changed, no write will be performed). This method of only making incremental saves improves          the occupancy level of the size-restricted Flash.     Stack Context Data          The NXP ZigBee PRO stack automatically saves its own context data from RAM to Flash when certain data items change. This data will not be encrypted. 3.2   Recovering Data from Flash       Application data and stack context data are loaded from the Flash to RAM as described below.     Application Data             During a cold start or a warm start without memory held, once the PDM module has been initialized (see Section 2.2), PDM_eReadDataFromRecord() must be called             for each record of application data in Flash that needs to be copied to RAM.     Stack Context Data             The function PDM_eReadDataFromRecord(), described above, is not used for records of stack context data. Loading this data from the Flash to RAM is handled             automatically by the stack (provided that the PDM has been initialized). 3.3   Deleting Data in Flash         All records (application data and stack context data) in the Flash can be deleted using the function PDM_vDeleteAllDataRecords().          Caution: You are not recommended to delete records of ZigBee PRO stack context data by calling PDM_vDeleteAllDataRecords() before a rejoin of the same secured          network. If these records are deleted, data sent by the node after the rejoin will be rejected by the destination node since the frame counter has been reset on the source          node. For more information and advice, refer to the “Application Design Notes” appendix in the ZigBee 3.0 Stack User Guide. 4.    PDM Features PDM offers a function that can be used to search for a specific record by using the 16-bit record ID. This function is called PDM_GetNVMTableEntry() and the required parameters are the record ID and an output pointer for the found entry. Another available PDM feature is providing a mechanism to safely write the data to NVM. This is done by calling the function PDM_vCompletePendingOperations(), which calls the appropriate NVM function that is used to complete all writings to NVM before any other operation. As an example, user can use this function to make sure that the data is written to the NVM before a reset.
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This post explains the implementation to operate the KW36 MCU on VLPR when the clocking mode is BLPE or BLPI. It's also included the explanation on how to configure clocks for BLPE and BLPI modes. For this example, the beacon demo from the wireless examples of the FRDM-KW36 is used. FRDM-KW36 SDK can be downloaded from MCUXpresso webpage. A recommended option to configure clock modes is "Config Tools" from MCUXpresso. Config Tools is embedded to MCUXpresso IDE, or you can download Config Tools from this LINK if you are using other supported IDE for this tool. MCUXpresso IDE is used in this example. Configure BLPE or BLPI clocking modes Select your proyect on MCUXpresso IDE, then open the clocks configuration window from Config Tools by clicking the arrow next to Config Tools icon from your MCUXpresso IDE, and then select "Open Clocks" as shown in Figure 1. Figure 1. Open Clocks from Config Tools using MCUXpresso IDE. A clocks diagram window will be opened. To configure the clock modes just select your option "BLPI" or "BLPE" on MCG Mode as shown in Figure 2. Clock will be automatically configured. Figure 2. MCG Mode selection. Now let's configure the appropiate clocks for Core clock and Bus clock to run in VLPR. Figure 3 taken from KW36 Reference Manual shows achievables frequencies when MCU is on VLPR.  Figure 3. VLPR clocks. Core clock should be 4MHz for BLPE and BLPI clocking modes, and Bus clock should be 1MHz for BLPE and 800kHz for BLPI.  Figure 4 shows clocks distribution for BLPE and Figure 5 for BLPI to operate with discussed frequencies. Figure 4. Clock distribution - VLPR and BLPE. Figure 5. Clock distribution - VLPR and BLPI. Press "Update Project" (Figure 6) to apply your new clock configuration to your firmware, then change perspective to "Develop" icon on right corner up to go to your project (See Figure 7). Compile your project to apply the changes. Figure 6. Update Project button. Figure 7. Develop button. At this point your project is ready to work with BLPE or BLPI clocks modes. Now, let's configure MCU to go to VLPR power mode. Configure VLPR mode VLPR mode can be configured using Config Tools too, but you may have an error trying to configure it when BLPE mode, this is because  CLKDIV1 register cannot be written when the device is on VLPR mode. For this example, let's configure MCU into VLPR mode by firmware. Follow next steps to configure KW36 into VLPR power mode: 1. Configure RF Ref Oscillator to operate in VLPR mode. By default, the RF Ref Osc it's configured to operate into RUN mode. To change it to operate on VLPR mode just change the bits  RF_OSC_EN from Radio System Control from 1 (RUN) to 7 (VLPR). Figure 8 taken from KW36 Reference Manual shows RF_OSC_EN value options from  Radio System Control.    Figure 8. RF_OSC_EN bits from Radio System Control register. Go to clock_config.c file in your MCUXpresso project and search for "BOARD_RfOscInit" function. Change the code line as shown in Figure 9 to configure RF Ref Osc to work into VLPR mode. You may see a window asking if you want to make writable the read-only file, click Yes. Figure 9. Code line to configure RF Ref Osc to work into VLPR mode Be aware that code line shown in Figure 9 may change with updates done in clocks using Config Tools. Note 2. Configure DCDC in continuous mode. According to KW36 Reference Manual, the use of BLPE in VLPR mode is only feasible when the DCDC is configured for continuous mode. First, let's define  gDCDC_Enabled_d flag to 1 on preprocesor. With this implementation, the use of DCDC_Init function will be enabled, and it's where we going to add the code line to enable continuous mode. Right click on your project, select Properties, go to Settings under C/C++ Build, then Preprocessor under MCU C Compiler (Figure 10).   Figure 10. MCUXpresso Preprocessor   Click on add button from Defined symbols, write gDCDC_Enabled_d =1 and click OK to finish   (Figure 11).  Re-compile your project. Figure 11. MCUXpresso Defined symbols   Now let's set  VLPR_VLPW_CONFIG_DCDC_HP bits to 1 from DCDC_REG0 register. Figure 12 was taken from KW36 Reference Manual. Figure 12. VLPR_VLPW_CONFIG_DCDC_HP values. Go to DCDC_Init  function and add the next code line to enable continuous mode on DCDC: DCDC->REG0 |= DCDC_REG0_VLPR_VLPW_CONFIG_DCDC_HP_MASK; Figure 13 shows the previous code line implemented in firmware project inside of DCDC_Init function . Figure 13. Continuous mode for DCDC enabled. 3. Configure MCU into VLPR mode To finish, let's write the code to configure MCU into VLPR power mode. Copy and paste next code just after doing implementation described on step 1 and 2: #if (defined(FSL_FEATURE_SMC_HAS_LPWUI) && FSL_FEATURE_SMC_HAS_LPWUI) SMC_SetPowerModeVlpr(SMC, false); #else SMC_SetPowerModeVlpr(SMC); #endif while (kSMC_PowerStateVlpr != SMC_GetPowerModeState(SMC)) { } It may be needed to add the SMC library: #include "fsl_smc.h" The code is configuring MCU into VLPR mode with bits RUNM from SMC_PMCTRL register (Figure 14) and then check if it was correctly configured by reading status bits PMSTAT from SMC_PMSTAT register (Figure 15) Figure 14. RUNM bits from  SMC_PMCTRL register. Figure 15. PMSTAT bits from  SMC_PMSTAT register. KW36 is ready to operate and BLPE or BLPI clocking modes with VLPR power mode.
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FRDM-KW36 Software Development Kit (SDK) includes drivers and examples of FlexCAN module for KW36 which can be easily configured for a custom communication. For example, if user want to change the default baud rate from FlexCAN driver demo examples then the only needed change is the default value on " config->baudRate " and " config->baudRateFD" from "FLEXCAN_GetDefaultConfig" function (See Figure 1). Segments within a bit time will be automatically configured to obtain the desired baud rate. By default, demos are configured to work with CAN FD communication. Figure 1. FRDM-KW36's default baudrate from flexcan_interrupt_transfer driver example Even so, there are cases where segments within a bit time are not well configured and it's necessary that user configure segments manually. An example occurs by setting the maximum FD baud rate "3.2MHz" using the 32MHz xtal or "2.6MHz" using a 26MHz xtal where demo reports an error. See Figure 2. Figure 2. Error by setting maximum baud rate When this error occurs, the fix is on setting the timing config parameters correctly by including the definition of  SET_CAN_QUANTUM on application source file (see Figure 3) and then declare and initialize the timing config parameters shown in Figure 4. Figure 3. SET_CAN_QUANTUM define Figure 4. Custom timing config parameters For this example we are going to show how to calculate timing config parameters in an scenario where a CAN FD communication is used with baud rate of 500kHz on nominal phase and 3.2MHz on FD phase. See Figure 5.  To do it, we need to calculate Time Quanta and value of segments within the bit time.    Figure 5. Custom CAN FD baudrate KW36 Reference Manual in chapter "37.4.8.7 Protocol timing" shows the segments within a bit time for CAN nominal phase configured in "CAN_CTRL1" register (see Figure 6), and segments for FD phase configured in CAN_FDCBT register (see Figure 7). Figure 6. Segment within a bit time for CAN nominal phase Figure 7. Segment within a bit time for CAN FD phase Before calculating the value of segments, first we need to calculate the Time Quanta which is the atomic number of time handled by the CAN engine. The formula to calculate Time Quanta is shown in Figure 8 taken from KW36 Reference Manual. Figure 8. Time Quanta Formula CANCLK can be selected by CLKSRC bits on CAN_CTRL1 register as shown in Figure 9, where the options are Peripheral clock=20MHz or Oscillator clock (16MHz if using 32MHz xtal or 13MHz if using 26MHz xtal). The recomiendation is to use the Oscillator clock due to peripheral clock can have jitter that affect communication.  Figure 9. CAN clocks To select the Oscillator clock, search for flexcanConfig.clkSrc definition and set it to kFLEXCAN_ClkSrcOsc as shown in Figure 10. Figure 10. CANCLK selection Next step is selecting the  PRESDIV value for nominal phase and FPRESDIV for FD phase. You have to select the right value to achieve the TQ needed to obtain the configured baudrate. For this example, let's set FPRESDIV value to 0 and PRESDIV value to 3. TQ calculation for nominal phase: TQ = (PRESDIV + 1) / CANCLK = (3 + 1) / 16000000 = 0.00000025 TQ calculation for FD phase: TQ = (FPRESDIV + 1) / CANCLK = (0 + 1) / 16000000 = 0.0000000625 The bit rate, which defines the rate of CAN message is given by formula shown in Figure 11 taken from KW36 Reference Manual. Figure 11. CAN Bit Time and Bit Rate Formulas With this info and with our TQ calculated, we can deduce that we need: For Nominal phase: 8 = Number of Time Quanta in 1 bit time For FD phase: 5 = Number of Time Quanta in 1 bit time Now, let's define the value of segments. For nominal phase: Bit Time =  (number of Tq in 1 bit time) x Tq CAN Bit Time = (1 + (PROPSEG + PSEG1 + 2) + (PSEG2 + 1) ) x Tq CAN Bit Time = (1 + (1 + 2  + 2) + (1 + 1) ) x Tq = 8 x  0.00000025  =  Baud rate = 1/  CAN Bit Time = 500KHz For FD phase: CAN Bit Time = (number of Tq in 1 bit time) x Tq CAN Bit Time = (1 + (FPROPSEG + FPSEG1 + 1) + (FPSEG2 + 1) ) x Tq CAN Bit Time = (1 + (0 + 1 + 1) + (1 + 1) ) x Tq = 5 x Tq =  0.0000003125 Bit Rate = 1/CAN Bit Time = 1 / 0.0000003125 =  3.2MHz To finish, just update the calculated values on your firmware on flexcanConfig.timingConfig structure.  Notes: FRDM-KW36 Software Development Kit (SDK) can be downloaded from MCUXpresso webpage. FlexCAN driver examples are located in path: "SDK_2.2.0_FRDM-KW36\boards\frdmkw36\driver_examples" from your downloaded FRDM-KW36 SDK. Take in consideration that not all the baud rates are achievables and will depend on the flexcan clock and segment values used.
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By default, FRDM-KW36 board includes a 32MHz XTAL (YI) as shown in Figure 1 but there are cases where a 26MHz XTAL is needed instead of 32MHz XTAL for FRDM-KW36 or a custom KW36 board.   Figure 1. 32MHz XTAL from FRDM-KW36 schematics Wireless connectivity demos from FRDM-KW36 Sofware Development Kit are configured to run with a 32MHz XTAL by default, but it's very easy to modify the software to operate with a 26MHz XTAL. Follow next steps to configure a FRDM-KW36 wireless connectivity demo to operate with a 26MHz XTAL: 1. In clock_config.h file, change BOARD_XTAL0_CLK_HZ define from 32000000U to 26000000U as shown in Figure 2.   Figure 2. BOARD_XTAL0_CLK_HZ define in clock_config.h 2. Add RF_OSC_26MHZ=1 line in preprocessor: If using IAR IDE: Right click on your project, then click options (Figure 3). Figure 3. IAR project options Go to C/C++ Compiler tab, then Preprocessor, and add  RF_OSC_26MHZ=1 line in defined symbols window (Figure 4). Figure 4. IAR Preprocessor If using MCUXpresso IDE: Right click on your project, select Properties, go to Settings under C/C++ Build, then Preprocessor under MCU C Compiler (Figure 5). Figure 5. MCUXpresso Preprocessor Click on add button from Defined symbols, write  RF_OSC_26MHZ=1 and click OK to finish (Figure 6). Figure 6. MCUXpresso Defined symbols To finish, re-compile your project and it will be ready to operate with a 26MHz XTAL. FRDM-KW36 SDK can be downloaded from the MCUXpresso webpage.
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This document describes how to update and sniff Bluetooth LE wireless applications on the USB-KW41 Programming the USB-KW41 as sniffer   It was noticed that there are some issues trying to follow a Bluetooth LE  connection, even if the sniffer catches the connection request. These issues have been fixed in the latest binary file which can be found in the Test Tool for Connectivity Products 12.8.0.0 or newest.   After the Test Tool Installation, you’ll find the sniffer binary file at the following path. C:\NXP\Test Tool 12.8.1.0\images\KW41_802.15.4_SnifferOnUSB.bin   Programming Process. 1. Connect the  USB-KW41Z to your PC, and it will be enumerated as Mass Storage Device 2. Drag and drop the " KW41_802.15.4_SnifferOnUSB.bin " included in Test tool for Connectivity Products.    "C:\NXP\Test Tool 12.8.0.0\images\KW41_802.15.4_SnifferOnUSB.bin" 3. Unplug the device and old the RESET button of the USB-KW41Z, plug to your PC and the  K22 will enter in a bootloader mode. 4.  Drag and drop the   " sniffer_usbkw41z_k22f_0x8000.bin "   included in Test tool for Connectivity Products.    "C:\NXP\Test Tool 12.8.5.9\images\sniffer_usbkw41z_k22f_0x8000.bin" 5. Then, unplug and plug the USB-KW41Z to your PC.                                                                                                          Note : If the USB-KW41 is not enumerated as Mass Storage Device, please look at the next thread https://community.nxp.com/thread/444708   General Recommendations   Software Tools  Kinetis Protocol Analyzer Wireshark version (2.4.8) Hardware Tools 1 USB-KW41 (updated with KW41_802.15.4_SnifferOnUSB.bin from Test Tool 12.8 or later)   The Kinetis Protocol Analyzer provides the ability to monitor the Bluetooth  LE  Advertisement Channels. It listens to all the activity and follows the connection when capturing a Connection Request.   Bluetooth  LE  Peripheral device transmits packets on the 3 advertising channels one after the other, so the USB-KW41 will listen to the 3 channels one by one and could or not catch the connection request. Common use case The USB-KW41 will follow the Bluetooth  LE  connection if the connection request happens on the same channel that It is listening. If is listening to a different channel when the connection request is sent, it won't be able to follow it. A Simple recommendation is the Bluetooth  LE  Peripheral should be set up to send the adv packets only to one channel and the sniffer just capturing on the same channel.   Improvement Use 3 USB-KW41, each of them will be dedicated to one channel and will catch the connection request.   Configure Kinetis Protocol Analyzer and Wireshark Network Analyzer Note: For better results, address filter can be activated. When you are capturing all the packets in the air, you will notice 3 adv packets. Each packet will show the adv channel that is getting the adv frame. One of the three sniffers will capture the Connection Request. In this case, it happens on channel 38.   You will be able to follow the connection, see all the data exchange.   For a better reference, you can look at the USB-KW41 Getting Started Hope it helps Regards, Mario
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High level description to enable a Linux + KW41Z Border Router. Similar to how it’s shown for the K64 solution in the Kinetis Thread Stack Application Development Guide.   Configure the OpenWrt router to assign the IPv6 ULA prefix 2001:2002:2003::/48. On the LAN network, the router distributes addresses from range 2001:2002:2003::/60 Plug an Ethernet cable between the OpenWrt router and the Linux box. Before creating the Thread network, the Linux box has a global address on its eth interface from range 2001:2002:2003::/60. After creating the Thread network, the BR configures on its Serial TAP interface an address from range 2001:2002:2003::/60. On its 6LoWPAN interface, the BR configures an address from range 2001:2002:2003:c::/64. This is achieved with DHCPv6 prefix delegation - the router is requested to assign a new prefix space to be used by the Thread network. The forth segment in the IPv6 range might be 2, 4, 8 or c, depending of the number of DHCP-PD requests made to the router. After 4 attempts, the router will not lease any other prefixes for some time. In order to force that, you'd require to restart the odhcpd deamon in the OpenWrt router with the following command: /etc/init.d/odhcpd restart . Join the router eligible device, which configures an address in 2001:2002:2003::1/60. We then ping the "Internet" (the LAN interface on the OpenWrt router) and it works. “threadtap0” interface must be bridged with an uplink interface connected to an OpenWrt DHCPv6-PD enabled router; it will act identically as the K64F solution.   Setup Linux PC (Ubuntu) OpenWrt AP/Router with DHCPv6-PD support (OpenWrt version used in this guide: OpenWrt Chaos Calmer 15.05.1) For reference, hardware used on this guide:  TP-Link Model TL-WR741ND 150Mbps Wireless N Router OpenWRT firmware supports multiple hardware available at https://openwrt.org/ 1 FRDM-KW41Z (Host Controlled Device, connected to Linux) 1 FRDM-KW41Z (Router Eligible Device or any joiner device) Thread version 1.1.1.20 (from SDK builder at mcuxpresso.nxp.com)   Host Controlled Device firmware, make sure the following macros are enabled : THR_SERIAL_TUN_ROUTER                       /source/config.h     -> Enables TAP interface by default (not TUN) THR_SERIAL_TUN_ENABLE_ND_HOST     /app/common/app_serial_tun.h   OpenWRT router Configure IPv6 ULA-Prefix:   Linux Copy HSDK folder Create 'threadtap0' TAP interface: …/host_sdk/hsdk/demo#    sudo bash make_tap.sh Use "Thread_Shell" or modify “Thread_KW_Tun” demo to enable the SERIAL_TAP macro …/host_sdk/hsdk/demo#   nano Thread_KW_Tun.c #define SERIAL_TAP 0   modify to:  #define SERIAL_TAP  1         Note : For demo purposes, the "Thread_Shell" demo is recommended, it already uses TAP by default and allows input commands. If this is not required and only the TAP bridge is to be used, use the Thread_KW_Tun demo. Bridge the interfaces; assuming eno1 is the interface connected directly to OpenWrt: # brctl addbr br0 # brctl addif br0 eno1 # brctl addif br0 threadtap0 # ifconfig br0 up Note : (Optional) Addresses on the bridged interfaces are lost and need to be reconfigured on the actual bridge. In this example, after bridging eno1 (interface to OpenWrt router), you’d have to run #dhclient br0 to get an IPv4 address on br0 for SSH to the router and/or #dhclient -6 br0 to get an IPv6 address to the br0 interface. There's a note here https://wiki.archlinux.org/index.php/Network_bridge#With_bridge-utils  about this.   Build C demos …/host_sdk/hsdk/demo#    make Run Thread_Shell or Thread_KW_Tun demo. …/host_sdk/hsdk/demo#    sudo ./bin/Thread_Shell /dev/ttyACM0 threadtap0 25 or …/host_sdk/hsdk/demo#    sudo ./bin/Thread_KW_Tun /dev/ttyACM0 threadtap0         Note: Try to run the demo without parameters to get some help on the input parameters   ifconfig Thread_Shell demo Thread_KW_Tun demo Joiner FRDM-KW41Z (shell) Join the Thread network Verify IP addresses Ping Eth LAN interface on OpenWrt router to verify “Internet” connectivity  Regards, JC
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