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Kinetis Microcontrollers Knowledge Base

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The following document contains a list of documents , questions and discussions that are relevant in the community based on the amount of views they are receiving each month. If you are having a problem, doubt or getting started in Kinetis processors or MCUXpresso, you should check the following links to see if your doubt have been already solved in the following documents and discussions. MCUXpresso MCUXpresso Supported Devices Table FAQ: MCUXpresso Software and Tools  Getting Started with MCUXpresso and FRDM-K64F  Generating a downloadable MCUXpresso SDK v.2 package  Quick Start Guide – Using MCUXpresso SDK with PINs&CLOCKs Config Tools  Moving to MCUXpresso IDE from Kinetis Design Studio Kinetis Microcontrollers Guides and examples Using RTC module on FRDM-KL25Z  Baremetal code examples using FRDM-K64F Using IAR EWARM to program flash configuration field Understanding FlexIO  Kinetis K80 FAQ How To: Secure e-mail client (SMTP + SSL) with KSDK1.3 + WolfSSL for FRDM-K64F  Kinetis Bootloader to Update Multiple Devices in a Network - for Cortex-M0+  PIT- ADC- DMA Example for FRDM-KL25z, FRDM-K64F, TWR-K60D100 and TWR-K70  USB tethering host (RNDIS protocol) implementation for Kinetis - How to use your cellphone to provide internet connectivity for your Freedom Board using KSDK Write / read the internal flash Tracking down Hard Faults  How to create chain of pbuf's to be sent? Send data using UDP.  Kinetis Boot Loader for SREC UART, SD Card and USB-MSD loading  USB VID/PID numbers for small manufacturers and such like  Open SDA and FreeMaster OpenSDAv2  Freedom OpenSDA Firmware Issues Reported on Windows 10 Let´s start with FreeMASTER!  The Kinetis Design Studio IDE (KDS IDE) is no longer being actively developed and is not recommended for new designs. The   MCUXpresso   IDE has now replaced the Kinetis Design Studio IDE as the recommended software development toolchain for NXP’s Kinetis, LPC and i.MX   RT Cortex-M based devices. However, this documents continue to receive considerable amount of views in 2019 which means it could be useful to some people. Kinetis Design Studio New Kinetis Design Studio v3.2.0 available Using Kinetis Design Studio v3.x with Kinetis SDK v2.0  GDB Debugging with Kinetis Design Studio  KDS Debug Configurations (OpenOCD, P&E, Segger) How to use printf() to print string to Console and UART in KDS2.0  Kinetis Design Studio - enabling C++ in KSDK projects  Using MK20DX256xxx7 with KDS and KSDK  Kinetis SDK Kinetis SDK FAQ  Introducing Kinetis SDK v2  How to: install KSDK 2.0  Writing my first KSDK1.2 Application in KDS3.0 - Hello World and Toggle LED with GPIO Interrupt 
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Introduction What is a gated timer and why would I need one? A gated timer is a timer whose clock is enabled (or "gated") by some external signal.  This allows for a low code overhead method of synchronizing a timer with an event and/or measuring an event. This functionality is not commonly included on Freescale microcontroller devices (this functionality is only included on d evices that are equipped with the upgraded TPM v2 peripheral; currently K66, K65, KL13, KL23, KL33, KL43, KL03) but can be useful in some situations.  Some applications which may find a gated timer useful include asynchronous digital sampling, pulse width duty cycle measurement, and battery charging. How do I implement a gated timer with my Kinetis FTM or TPM peripheral? To implement a true gated timer with a Kinetis device (that does not have the TPM v2 peripheral), additional hardware will be required to implement the enable/disable functionality of a gated timer.  This note will focus on two different ways (low-true and high-true) to implement a gated timer.  The method used will depend on the requirements of your application. Implementing a gated timer for Kinetis devices without the TPM v2 peripheral requires the use of a comparator and a resistive network to implement a gated functionality (NOTE:  Level shifters could be used to replace the resistive network described; however, a resistive network is likely more cost effective, and thus, is presented in this discussion).  Figure 1 below is the block diagram of how to implement a gated timer functionality.  The theory behind this configuration will be explained in later sections. Theory of Operation Comparator and resistive network implementation The comparator is the key piece to implementing this functionality. For those with little experience with comparators (or need a refresher), a comparator is represented by the following figure.  Notice that there are three terminals that will be of relevance in this application: a non-inverting input (labeled with a '+' sign), an inverting input (labeled with a '-' sign), and an output. A comparator does just what the name suggests: it compares two signals and adjusts the output based on the result of the comparison.  This is represented mathematically in the figure below. Considering the above figure, output of the comparator will be a  logic high when the non-inverting input is at a higher electric potential than the inverting input.  The output will be a logic low if the non-inverting input is at a lower electric potential than the inverting input.  The output will be unpredictable if the inputs are exactly the same (oscillations may even occur since comparators are designed to drive the output to a solid high or solid low).  This mechanism allows the clock enable functionality that is required to implement a gated timer function provided that either the non-inverting or inverting input is a clock waveform and the opposite input is a stable logic high or low (depending on the desired configuration) and neither input is ever exactly equal.  Comparator Configurations There are two basic signal configurations that an application can use to enable the clock output out of the comparator: low-true signals and high-true signals.  These two signals and some details on their implementation are explained in the following two sections.  Low-true enable A low-true enable is an enable signal that will have zero electric potential (relative to the microcontroller) or a "grounded" signal in the "active" state.  This configuration is a common implementation when using a push button or momentary switch to provide the enable signal.  When using this type of signal, you will want to connect the enable signal to the non-inverting input of the comparator, and connect the clock signal to the inverting input. The high level of the enable signal should be guaranteed to always be the highest voltage of the input clock plus the maximum input offset of the comparator. To find the maximum input offset of the comparator, consult the device specific datasheet.  See the figure below to see a graphical representation of areas where the signal will be on and off. The external hardware used should ensure that the low level of the enable signal never dips below the lowest voltage of the input clock plus the maximum input offset of the comparator. The following figure displays one possible hardware configuration that is relatively inexpensive and can satisfy these requirements. High-true enable A high-true enable is an enable signal that will have an electric potential equal to VDD of the microcontroller in the "active" state.  This configuration is commonly implemented when the enable signal is provided by an active source or another microcontroller.  When interfacing with this type of signal, you will want to connect the enable signal to the inverting input of the comparator, and connect the clock signal to the non-inverting input.  When the comparator is in the inactive state, it should be at or below the lowest voltage of the clock signal minus the maximum input offset of the comparator.  Refer to the following figure for a diagram of the "on" and "off" regions of the high true configurations. The external hardware will need to guarantee that the when the enable signal is in the active state, it does not rise above the highest voltage of the clock signal minus the maximum input offset of the comparator. The following figure displays one possible hardware configuration that is relatively inexpensive and can satisfy these requirements. Clocking Options Clocking waveform requirements will vary from application to application.  Specifying all of the possibilities is nearly impossible.  The point of this section is to inform what options are available from the Kinetis family and provide some insight as to when it might be relevant to investigate each option. The Kinetis family provides a clock output pin for most devices to allow an internal clock to be routed to a pin.  The uses for this option can vary.  In this particular scenario, it will be used to provide the source clock for the comparator clock input. Here are the most common clock output pin options across the Kinetis K series devices.  (NOTE:  If the application requires a clock frequency that the CLKOUT signal cannot provide, a separate FTM or TPM instance or another timer module can be used to generate the required clock.) In the Kinetis L series devices, the following options will be available. The clock option selected should be the slowest allowable clock for the application being designed.  This will minimize the power consumption of the application.  For applications that require high resolution, the Bus, Flash, or Flexbus clock should be selected (note that the Flexbus clock can provide an independently adjustable clock, if it is not being used in the application, as it is always running).  However, if the target application needs to be more power efficient, the LPO or MCGIRCLK should be used.  The LPO for the Kinetis devices is a fixed 1 kHz frequency and will, therefore, only be useful in applications that require millisecond resolutions.
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Problem Analysis and solutions for booting from ROM BOOTLOADER in KL series 1 Abstract      When customer use the kinetis chip KL43, KL27 and KL17 which flash size is above 128K, they have found a problem that if the code boot from the ROM instead of the flash, the application code about the LPUART and I2C will run in abnormal state, especially when use PTA1 as the  LPUART receive pin, UART transmit function has no problem, but when the PTA1 receive the UART data, the code will run to the abnormal area and can’t return back, the code will be crash. This problem only happens on booting from the ROM and the uart and i2c peripheral are enabled in BCA 0x3d0 address, uart peripheral enablement in BCA area will influence the application PTA1 uart receive, i2c peripheral enablement in BCA area will influence the i2c0 module in the application code. If booting from the flash or booting from ROM but the uart and I2C peripheral are disabled in the BCA 0x3d0 address, everything is working ok in the application code.      This document will take the UART problem as an example, give details of the problem reproduction, testing, analysis and the solutions. The I2C problem is the same when booting from the ROM bootloader. 2 Problem reproduction and analysis  Testing preparation: IDE: KDS 和IAR Hardware: FRDM-KL43 Software: 3.0 and KSDK2.0_FRDM-KL43      We mainly reproduce the uart receive problem in two ways: new KDS PE project based on KSDK1.3.0 and official newest sample code package KSDK2.0_FRDM-KL43. 2.1 Problem reproduction in new creating kds project Because the KSDK2.0 still doesn’t support the PE function in the KDS IDE, so we use the KSDK1.3.0 as the PE KSDK to create the new KDS project. 2.1.1 Create KDS KL43 project The new KDS PE project creating is very simple, here just describe the important points which is relate to the UART problem after booting from the ROM. At first create a new KDS PE project which is based on KSDK1.3.0, and choose the chip as MKL43Z256VLH4, select the MCG mode as HIRC, and configure core clock to 48Mhz, bus clock to 24Mhz. Then add the uart module fls_debug_console for testing, because the FRDM_KL43 is using PTA1 and PTA2, the console module can be configured like the following picture, after the module is configured, press the code generation button to generate the project code. Then add the simple code in file main.c main function for testing: char a; for (;;) {                 PRINTF( " test!\n" );                 a= GETCHAR();                 PUTCHAR(a);               } The code function is: printf the “test!” to the COM port in the PC, then wait the uart data, if receive the data, then printf the received data back and run this loop function again.   2.1.2 Add the BCA area    From the KL43 reference manual, we can get that, BCA start address is 0X3C0:     The KDS newly created project didn’t contain the BCA area in the link file, so we need to add this area in the link file and add the BCA data in the start file by ourselves. 2.1.2.1 Divide the BCA flash are in .ld file Add the following code to define the BCA start flash address and the flash size in the ProcessorExpert.ld memory area: m_bca                 (RX)  : ORIGIN = 0x000003C0, LENGTH = 0x00000040 Then add this code in the SECTIONS area:   .bca :            {              . = ALIGN(4);              KEEP(*(.bca)) /* Bootloader Configuration Area (BCA) */              . = ALIGN(4);            } > m_bca At last, the ld file is like this: For the ld file protection, we can change the ld file properties to read-only, then this file won’t be changed to the initial one after building. 2.1.2.2 Add the BCA data in the start file      After add the BCA flash area divide code, we still need to define the BCA data in the start file:    /* BCA Area */     .section .bca, "a"                 .ascii "kcfg"                            // [00:03] tag                 .long 0xFFFFFFFF // [07:04] crcStartAddress                 .long 0xFFFFFFFF // [0B:08] crcByteCount                 .long 0xFFFFFFFF // [0F:0C] crcExpectedValue                 .byte 0x03                                             // [10] enabledPeripherals  I2C and UART                 .byte 0xFF                                              // [11] i2cSlaveAddress                 .short 3000                           // [13:12] peripheralDetectionTimeout (milliseconds)                 .short 0xFFFF                        // [15:14] usbVid                 .short 0xFFFF                        // [17:16] usbPid                 .long 0xFFFFFFFF  // [1B:18] usbStringsPointer                 .byte 0xFF                                              // [1C] clockFlags                 .byte 0xFF                                              // [1D] clockDivider                 .byte 0xFF                                              // [1E] bootFlags                 .byte 0xFF                                              // [1F] reserved*/    More details, please refer to this picture:       So far, we have create the FRDM-KL43 test project which contains the BCA area, and boot from the ROM that can be modified in the flash address 0X40D, bit 6-7 in 0X40D is the BOOTSRC_SEL bits, 00 boot from flash, 10 and 11 boot from ROM, more details about the FOPT, please refer to Table 6-2. Flash Option Register (FTFA_FOPT) definition in reference manual.     2.1.3 Test result and analysis       Now, list the test result after booting from ROM or flash, and boot from ROM but enable the peripherals. Boot from: ROM peripheral Test Result Flash XX OK ROM 0XFF, enable all NO, UART can’t receive 0X08, enable USB Yes, UART can receive 0X04, enable SPI Yes, UART can receive 0X02, enable I2C Yes, UART can receive 0X01, enable LPUART NO, UART can’t receive      From the test result, we can reproduce the problem. The UART receive problem just happens on booting from ROM and the LPUART is enabled, when we run it with debugger, and test it step by step, we can find after the PTA1 have received the data, the code will run to the abnormal area. Note: when debug this code, please choose the JLINK as the debugger, because the P&E tool will protect the FOPT area automatically in the KDS IDE when do debugging, the code will still run from flash, so if customer use the P&E tool, they will found the PTA1 still can receive the data, this is not the real result, but the JLINK won’t protect FOPT area in the KDS IDE, it can reflect the real result.      After using the JLINK as the debugger, and we have found after PTA1 getting data or pulling low, the code will enter to the abnormal area like this:      We can get that the code run to the defaultISR, and display with USB_IRQHander, but this is not really the USB_IRQHander, just caused by the PC abnormal. Normally, it is caused by the missing of interrupt service function.       Now, we test the NVIC data to check which module interrupt caused this, the following picture is the result by enabling the LPUART and I2C peripheral in the ROM BCA area. We can find, even we didn’t do the cpu and peripheral initialization after booting from ROM, there still have peripheral be enabled, what the interrupt is enabled? From the definitive guide to the ARM Cortex-M0.pdf: NVIC_ISER = 0x40000100, Vector46=IRQ30 and vector24=IRQ8 is enabled, it should be not disabled after booting from the ROM. Now check the KL43 reference manual, Table 3-2. Interrupt vector assignments, we can get that the I2C0 and PORTA interrupt is enabled. Checking the PORTA register before do the cpu and peripheral initialization, PTA1 is enabled the port interrupt, and choose Flag and Interrupt on falling-edge.     This can tell us why the PTA1 pin have the problem of uart receive data or give a falling edge in PTA1 will run abnormal, because in default, even we configure the PTA1 as the uart receive function, but the code didn’t clear IRQ and NVIC register, when the signal happens on PTA1 pin, it will caused the PORTA interrupt, but we didn’t add the PORTA interrupt ISR function, it is also not useful to us, then PC don’t know where to go, so it will run abnormal, enter the defaultISR, and can’t recover. If you have interest, you can add the PORTA_IRQHandler function, you will find the code will run to this function. 2.2 Problem reproduction in KSDK2.0 IAR project  Test project: SDK_2.0_FRDM-KL43Z\boards\frdmkl43z\demo_apps\hello_world  Test the official project just to make sure, it is really the chip hardware function, not only the problem from new generated code in KDS.   Because the IAR IDE will protect the 0X400 area, then if we want to modify the FOPT, we need to modify the .board, add –enable_config_write at first.    Then modify the FOPT in startup_MKL43Z.s: __FlashConfig         DCD 0xFFFFFFFF         DCD 0xFFFFFFFF         DCD 0xFFFFFFFF         DCD 0xFFFFFFFE   ; 0xFFFF3FFE   __FlashConfig_End   Because the BCA peripheral area is in default as 0XFF, it enables all the peripheral, we don’t need to define the BCA area independently.  For getting the real test result, we add the NVIC and PORTA_PCR1 register printf code in the main function,    PRINTF("PORTA_PCR1=%X \n", PORTA->PCR[1]);    PRINTF("NVIC=%X \n", NVIC->ICER[0U]); And download the modified KSDK sample code to the chip, after testing, we get this result: hello world. PORTA_PCR1=A0205 NVIC=40000100 It is the same result as the new created project after booting from the ROM, PORTA interrupt and I2C interrupt is enabled, and it caused the PTA1 receive data problem.  3 Solutions and test result 3.1 Solutions      From the Chapter 2 testing and analysis, we can get that UART receive problem is caused by the PORT interrupt and NVIC is enabled after booting from the ROM, this should be caused by exiting the ROM, the ROM forget to disable it. We also can find some descriptions from the KL43 reference manual page 211: So, if customer want to solve this problem, to avoid the application enter to the abnormal area, we can disable the NVIC in the application code like this, the I2C NVIC is the same:     NVIC_DisableIRQ(8);//disable I2C0 interrupt     NVIC_DisableIRQ(30); //disable PTA interrupt 3.2 Test result   From the test result after adding the NVIC I2C and PORTA disable code, we can get the uart can works ok, if you have interest to test, the I2C will also work ok. 4 Conclusion When customer use the kinetis chip KL43, KL27 and KL17 which flash size is above 128K, and want to boot from the ROM and enable the LPUART and I2C in BCA area, please add the NVIC I2C(IRQ8) and PORTA(IRQ30) disable code in the application code:     NVIC_DisableIRQ(8);//disable I2C0 interrupt     NVIC_DisableIRQ(30); //disable PTA interrupt So far, I just find KL43, KL27 and KL17 which flash size is above 128K have this problem, other kinetis chip which have ROM bootloader don’t have this problem.
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        在我们嵌入式工程应用中,中断作为最常用的异步手段是必不可少的,而且在一个应用程序中,一个中断往往是不够用的,多个中断混合使用甚至多级中断嵌套也经常会使用到,而这样就涉及到一个中断优先级的问题。         以我们最熟悉的Cortex-M系列为例,我们知道ARM从Cortex-M系列开始引入了NVIC的概念(Nested Vectors Interrupts Controller),即嵌套向量中断控制器,以它为核心通过一张中断向量表来控制系统中断功能,NVIC可以提供以下几个功能: 1)可嵌套中断支持; 2)向量中断支持; 3)动态优先级调整支持; 4)中断可屏蔽。         抛开其他不谈,这里我们只说说中断优先级的问题。我们知道NVIC的核心工作原理即是对一张中断向量表的维护上,其中M4最多支持240+16个中断向量,M0+则最多支持32+16个中断向量, 而这些中断向量默认的优先级则是 向量号越小的优先级越高 ,即从小到大,优先级是递减的。但是我们肯定不会满足于默认的状态(人往往不满足于约束,换句俗话说就是不喜欢按套路出牌,呵呵),而NVIC则恰恰提供了这种灵活性,即支持动态优先级调整,无论是M0+还是M4除了3个中断向量之外(复位、NMI和HardFault,他们的中断优先级为负数,它们3个的优先级是最高的且不可更改),其他中断向量都是可以动态调整的。         不过需要注意的是, 中断向量表的前16个为内核级中断,之后的为外部中断 ,而内核级中断和外部中断的优先级则是由两套不同的寄存器组来控制的,其中内核级中断由SCB_SHPRx寄存器来控制(M0+为SCB_SHPR[2:3],M4为SCB_SHPR[1:3]),外部中断则由NVIC_IPRx来控制(M0+为NVIC_IPR[0:7],M4为NVIC_IPR[0:59]),如下图所示: M0+中断优先级寄存器: M4中断优先级寄存器:         其中M4所支持的动态优先级范围为 0~15 (8位中只有高四位[7:4]才有效),而M0+所支持的动态优先级范围则为 0~3 (8位中只有高两位[7:6]才有效),而且秉承着号越小优先级越高的原则(0最高,15或3为最小) ,同时也间接解释了为什么复位(-3)、NMI(-2)和HardFault(-1)优先级最高的原因,很简单,人家都是负的了,谁还能比他们高,呵呵,而且这三位中复位优先级最高,NMI其次,HardFault最低(这个最低仅限于这三者)。 下面给出个ARM CMSIS库中关于M0+和M4中断优先级设置的API函数 NVIC_SetPriority(IRQn_Type IRQn, uint32_t priority) 实现供大家来参考: M0+: NVIC_SetPriority(IRQn_Type IRQn, uint32_t priority) {   if(IRQn < 0) {     SCB->SHP[_SHP_IDX(IRQn)] = (SCB->SHP[_SHP_IDX(IRQn)] & ~(0xFF << _BIT_SHIFT(IRQn))) |         (((priority << (8 - __NVIC_PRIO_BITS)) & 0xFF) << _BIT_SHIFT(IRQn)); }  /* set Priority for Cortex-M  System Interrupts */   else {     NVIC->IP[_IP_IDX(IRQn)] = (NVIC->IP[_IP_IDX(IRQn)] & ~(0xFF << _BIT_SHIFT(IRQn))) |         (((priority << (8 - __NVIC_PRIO_BITS)) & 0xFF) << _BIT_SHIFT(IRQn)); }   /* set Priority for device specific Interrupts  */ } M4: void NVIC_SetPriority(IRQn_Type IRQn, uint32_t priority) {   if(IRQn < 0) {     SCB->SHP[((uint32_t)(IRQn) & 0xF)-4] = ((priority << (8 - __NVIC_PRIO_BITS)) & 0xff); } /* set Priority for Cortex-M  System Interrupts */   else {     NVIC->IP[(uint32_t)(IRQn)] = ((priority << (8 - __NVIC_PRIO_BITS)) & 0xff);    }        /* set Priority for device specific Interrupts  */ }
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The Real Time Clock (RTC) module is the right tool when we want to keep tracking the current time for our applications. For the Freedom Platform (KL25Z) the RTC module features include: 32-bit seconds counter with roll-over protection and 32-bit alarm 16-bit prescaler with compensation that can correct errors between 0.12 ppm and 3906 ppm. Register write protection. Lock register requires POR or software reset to enable write access. 1 Hz square wave output. This document describes how to implement the module configuration. Also, how to modify the hardware in order feed a 32 KHz frequency to RTC module (it is just a simple wire link).     Hardware. The RTC module needs a source clock of 32 KHz. This source is not wired on the board; hence we need to wire it. Do not be afraid of this, it is just a simple wire between PTC3 and PTC1 and the good news are that these pins are external.   PTC1 is configured as the RTC_CLKIN it means that this is the input of source clock.     PTC3 is configured as CLKOUT (several options of clock frequency can be selected in SIM_SOPT2[CLKOUTSEL] register). For this application we need to select the 32 Khz clock frequency.                         RTC configuration using Processor Expert. First of all we need to set the configurations above-mentioned in Component Inspector of CPU component. Enable RTC clock input and select PTC1 in Pin Name field. This selects PTC1 as RTC clock input. MCGIRCLK source as slow in Clock Source Settings > Clock Source Setting 0 > Internal reference clock > MCGIRCLK source. This selects the 32 KHz clock frequency. Set ERCLK32K Clock Source to RTC Clock Input in Clock Source Settings > Clock Source Setting 0 > External reference clock > ERCLK32K Clock Source. This sets the RTC_CLKIN as the 32 KHz input for RTC module. Select PTC3 as the CLKOUT pin and the CLKOUT pin output as MCGIRCLK in Internal peripherals > System Integration Module > CLKOUT pin control. With this procedure we have a frequency of 32 KHz on PTC3 and PTC1 configured as RTC clock-in source. The MCG mode configurations in this case is PEE mode: 96 MHz PLL clock, 48 MHz Core Clock and 24 MHz Bus clock.   For the RTC_LDD component the only important thing is to select the ERCKL32K as the Clock Source. The image below shows the RTC_LDD component configuration for this application.   After this you only need to Generate Processor Expert Code and write your application.  The code of this example application can be found in the attachments of the post. The application prints every second the current time.     RTC bare-metal configuration. For a non-PEx application we need to do the same configurations above. Enable the internal reference clock. MCGIRCLK is active.          MCG_C1 |= MCG_C1_IRCLKEN_MASK; Select the slow internal reference clock source.          MCG_C2 &= ~(MCG_C2_IRCS_MASK); Set PTC1 as RTC_CLKIN and select 32 KHz clock source for the RTC module.          PORTC_PCR1 |= (PORT_PCR_MUX(0x1));              SIM_SOPT1 |= SIM_SOPT1_OSC32KSEL(0b10); Set PTC3 as CLKOUT pin and selects the MCGIRCLK clock to output on the CLKOUT pin.     SIM_SOPT2 |= SIM_SOPT2_CLKOUTSEL(0b100);     PORTC_PCR3 |= (PORT_PCR_MUX(0x5));   And the RTC module configuration could be as follows (this is the basic configuration just with seconds interrupt): Enable software access and interrupts to the RTC module.     SIM_SCGC6 |= SIM_SCGC6_RTC_MASK; Clear all RTC registers.   RTC_CR = RTC_CR_SWR_MASK; RTC_CR &= ~RTC_CR_SWR_MASK;   if (RTC_SR & RTC_SR_TIF_MASK){      RTC_TSR = 0x00000000; } Set time compensation parameters. (These parameters can be different for each application) RTC_TCR = RTC_TCR_CIR(1) | RTC_TCR_TCR(0xFF); Enable time seconds interrupt for the module and enable its irq. enable_irq( INT_RTC_Seconds - 16); RTC_IER |= RTC_IER_TSIE_MASK; Enable time counter. RTC_SR |= RTC_SR_TCE_MASK; Write to Time Seconds Register. RTC_TSR = 0xFF;   After this configurations you can write your application, do not forget to add you Interrupt Service Routine to the vector table and implement an ISR code.   In the attachments you can find two zip files: PEx application and non-PEx application.   I hope this could be useful for you,   Adrián Sánchez Cano. Original Attachment has been moved to: FRDM-KL25Z-RTC-TEST.zip Original Attachment has been moved to: FRDM-KL25Z-PEx-RTC.zip
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Introduction The K32L3A60VPJ1AT MCU is a next generation Kinetis dual core device.  This device brings processing and multi-tasking capabilities that legacy Kinetis devices did not support.  In addition, the K32L3A60VPJ1AT offers improved power consumption and security features.   Some important aspects of these security features lie in a nonvolatile information register (IFR) memory region and how this region is programmed.  The IFR memory region is a memory space with restricted access separate from the main array and is comprised of an erasable IFR region and a non-erasable IFR region.  The non-erasable IFR region contains the program once identifier and the version identifier.  The erasable IFR region holds the flash security, flash options, mass erase enable, and other such features that governs how the device behaves.  In legacy Kinetis devices, certain fields of the main flash array (flash addresses 0x400 - 0x40F) configured the IFR at boot time.  In the K32L3A60VPJ1AT however, the IFR memory region is no longer controlled in this manner.  This presents challenges when trying to configure these settings.  The purpose of this document is to explain how these settings can be changed and provide some options of how to make these changes.   The first step in configuring the IFR fields is understanding how the these fields are programmed via the hardware. IFR fields are programmed using a special flash command called the Program Index Command. Once programmed, the flash configuration values cannot be reprogrammed without first erasing these fields.  The only way to erase these values is via a mass erase.  This provides security in that the IFR values cannot be changed without erasing the user code as well.  In addition, changes to the user code image cannot affect the bootloader operation, ensuring that a secure boot function can be executed.  The procedure for writing the erasable IFR values is described here: Write FCCOB0 with the Program Index command (0x43). Write FCCOB1 with the Index to be programmed. The possible Indexes are listed in Erasable IFR Map table (table 16.4.1.2 in the K32L3A6 reference manual). Write FCCOB2 and FCCOB3 with 0x00 as they are not used with this command.  Write FCCOB4 - FCCOBB with the desired value.  (Note that not all of the indexes use all of the FCCOB fields.  Be sure to consult the Erasable IFR Map table for which FCCOB fields are used for the index you are programming).  Write 0x70 to the Flash status register (FSTAT) to clear any errors that might have been present from the last flash command. (Note that this command MUST be a byte write.) Write 0x80 to the Flash status register (FSTAT) to initiate the programmed flash command. Poll the FSTAT register until the CCIF bit field (bit field 7) is one ('1').  (Note that it may not be possible in your scripting language to do this, or it may just be easier to simply wait for the flash command to finish executing. In these cases, wait significantly longer than the typical Program Index command completion time of 110us.) After the IFR has been programmed, the IFR should be read back to verify that it completed correctly.  The process for this is as follows: Write FCCOB0 with the Read Index command (0x41). Write FCCOB1 with the Index to be read.   The possible Indexes are listed in Erasable IFR Map table (table 16.4.1.2 in the K32L3A6 reference manual). Write FCCOB2 - FCCOBB with 0. The results will be stored in FCCOB4 - FCCOBB so, these should be cleared to ensure correct results are received. Write 0x70  to the Flash status register (FSTAT) to clear any errors that might have been present from the last flash command. Note that this command MUST be a byte write. Write 0x80 to the Flash status register (FSTAT) to initiate the programmed flash command . Poll the FSTAT register until the CCIF bit field (bit field 7) is one ('1').  (Note that it may not be possible in your scripting language to do this, or it may just be easier to simply wait for the flash command to finish executing. In these cases, wait significantly longer than the maximum Read Index command completion time of 35us.) When using the Program Index Command, you must know which index you want to modify to create the correct flash commands.  The index list can be found in the IFR descriptions section of the Flash chapter in the K32L3A60VPJ1AT reference manual.   There are several different options for programming the FOPT fields. These options are: Using the Kinetis Flash Tool  Using blhost Debugger script Subroutine in user software Option #1: Kinetis Flash Tool Using the Kinetis Flash Tool is likely the most convenient method to change the IFR values.  The Kinetis Flash Tool uses either the UART or USB protocol to interface with the K32L3A6 bootloader and write the IFR fields desired. One of the biggest advantages for the Kinetis Flash Tool is that it provides a graphical interface for users to easily program the IFR fields. The following figure is a picture of the Kinetis Flash Tool and highlights the important input controls and tabs to be used when programming the IFR fields: This field is the Port set box.  It selects the interface (UART or USB) to be used when communicating to the bootloader.  This box also allows for configuration of the interface.  Consult the K32L3A6 reference manual for default configurations.   This is the Flash Utilities tab.  Select this tab to see the controls shown in this image.  This is the Index input field.  The Index of the IFR to program should be entered here.  This is the Hex digits field.  This value will be programmed at the IFR Index indicated in the Index field. The value here should be in hex format WITHOUT the preceding "0x".   This is the Byte Count field.  This tells the utility how many bytes to program and must be the byte count of that IFR field.  Consult the Erasable IFR Map table in the reference manual for the value of the specific IFR index to be programmed.   This is the Program button.  After all of the fields have been filled out, click this button to program the desired IFR location.  Option #2: BLHOST The MCUBoot package also includes a command line executable to interface with the bootloader.  This tool, blhost, can be used to program the IFR fields as well.  The "flash-program-once" command should be used to program the desired IFR location.  The syntax of this command is as follows: flash-program-once <index> <byteCount> <data> So for example, if you want to program the FOPT IFR field (record index 0x84) with 0xFFFFF3FF, the correct syntax using this command would be flash-program-once 0x84 4 FFFFF3FF After programming, the "flash-read-once" command can be used to read back and verify the programmed IFR field(s).  Below is an example using the previous IFR locations flash-read-once 0x84 4 Below is a full example of erasing the device, programming the FOPT IFR, and reading the FOPT IFR back from the command line using blhost.   Option #3: Debugger Script A simple debugger script is another convenient way to write the IFR values.  Debugger scripts are executed in the background of the debug session initiation process (therefore are hidden operations from the user) and typically can be edited easily using any text editor.  However, it can be cumbersome to change the value because this generally must done manually with each programming by the user. With that in mind, it is a good idea to have different connect scripts for different configurations The first step in using a debugger script is writing a debugger script.  The capabilities and syntax of a debugger script are dependent on your toolchain. For the purposes of this document, we will focus on MCUXpresso IDE.  MCUXpresso IDE uses the PokeXX and PeekXX (where XX is 8, 16, or 32 depending on whether you want to byte access, half-word or word access to the desired register) commands, which are debugger agnostic. So the same commands that work on a device will continue to work whether you are debugging with a JLink or CMSIS-DAP, or whatever other debugger you are using. Below is an example of a MCUXpresso connect script which writes the FOPT register and then reads it back for printing to the debug log.  5140 REM ====================Program FOPT=================================== 5150 Poke32 this 0x40023004 0x43840000 5160 REM Stuff FCCOB registers with desired FOPT value 5170 Poke32 this 0x40023008 v% 5171 s% = Peek32 this 0x40023008 5172 Print "New Val ";~s% 5180 Poke32 this 0x4002300c 0x00000000 5180 Poke8 this 0x40023000 0x70 5190 Poke8 this 0x40023000 0x80 5200 wait 1000 6000 REM ================== Read FOPT ===================================== 6001 REM Now read the FOPT back 6010 Poke32 this 0x40023004 0x41840000 6020 Poke32 this 0x40023008 0x00000000 6030 Poke32 this 0x4002300c 0x00000000 6040 Poke8 this 0x40023000 0x70 6050 Poke8 this 0x40023000 0x80 6060 wait 1000 6070 s% = Peek32 this 0x40023008 6080 Print "New FOPT Val ";~s%   Note in the above script that v% is the desired FOPT value and it has been defined in sections of the script not shown (at line 164).  162 REM This is the value to be written to the FOPT 164 v% = 0xfffff3ff After the script is written, MCUXpresso must be told to use the connect script.  This is done in the Debug Configurations window.  Assuming a debug configuration has already been created, click on the arrow next to the green bug icon and select Debug Configurations.   In the resulting dialog box, select the debug configuration you want to use, and select the Linkserver Debug tab.  In the Connect Script field, point MCUXpresso to the location of your connect script.   That's all that needs to be done in the IDE. The selected debug configuration should now be using the script which was written.   Some debuggers will allow standalone command line running of a script, such as a JLink debugger.  As the JLink is one of the more popular external debuggers that we encounter, an example of programming using this script has been provided below.   // Now Program the FOPT w4 0x40023004, 0x43840000 // The 43 selects the Program Index command. The 84 selects the FOPT IFR field. // Stuff the FCCOB registers (4-7) with the FOPT value we want to write. // ** (Boot Settings) ** w4 0x40023008, 0xfffff3ff // Write 0xFFFF_1FFF to boot the M4 from internal Flash. Asserting the NMI pin will force booting from the ROM. // Write FCCOB registers 8-B with dummy values. w4 0x4002300c, 0x00000000 // Write the FSTAT register to clear any errors that could have been present. w1 0x40023000, 0x70 // Launch the flash command. w1 0x40023000, 0x80 // Wait for the flash command to finish. Sleep 1 // Now Read the FOPT back w4 0x40023004, 0x41840000 // The 43 selects the Program Index command. The 84 selects the FOPT IFR field. // Stuff the FCCOB registers (4-7) with the FOPT value we want to write. // ** (Boot Settings) ** w4 0x40023008, 0x00000000 // Write 0xFFFF_F1FF to boot the M0+ from internal Flash. Asserting the NMI pin will force booting from the ROM. // Write FCCOB registers 8-B with dummy values. w4 0x4002300c, 0x00000000 // Write the FSTAT register to clear any errors that could have been present. w1 0x40023000, 0x70 // Launch the flash command. w1 0x40023000, 0x80 // Wait for the flash command to finish. Sleep 1 // Read the memory back to verify the FOPT settings that should be present after reset. mem32 40023000,4 Option #4: Subroutine in User Software Occasionally the requirements of your system will prevent implementation of any of the above methods to program the IFR values.  In these cases, you may need to implement your own subroutine to program the IFR.  The procedure to do this is essentially the same as in the debugger script methods, just written in code instead of an external script.  One key to remember is that you likely will need to erase the entire flash.  So this subroutine should be placed in RAM memory.  Because flash operations are executing, being in RAM will prevent certain flash errors from occurring.   Conclusion In summary, the IFR registers are nonvolatile information registers that govern certain behaviors of the K32L3A MCU.  The IFR is dividing into an  erasable IFR space and non-erasable IFR space, both of which are not a part of the main flash array.  Programming these values requires the use of special flash commands and requires that these values haven't been previously written since the last mass erase.  There are, in general, four different methods of programming the FOPT register settings.  The four methods are: Kinetis Flash Tool BLhost command line interface Debugger script  User software subroutine Each method has its advantages, therefore, you should pick the one that meets your needs and is most convenient. However with any of the methods chosen, the IFR values must not have been programmed before writing erasable IFR fields. It is best to perform a mass erase (which can be done using any of the methods presented in this document) before attempting to program any IFR fields.     
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The following file contains codewarrior code that was migrated from the IAR example code in the sample code package at the freescale webpage. It contains the following examples: adc_demo freedom_greem_led freedom_red_led lcd_rtc_lowpower PIT_basic sLCD_freedom uart_low_power_wu_dut Regards
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Hello all.   I would like to share an example project for FRDM-KL25Z board on which C90TFS Flash Driver was included to implement emulated EEPROM (Kinetis KL25 doesn’t have Flex Memory). It is based on the “NormalDemo” example project. A string of bytes is stored on the last page of the flash memory (address 0x1FC00-0x1FFFF), and then, it is overwritten with a different string.   The ZIP file also includes the “Standard Software Driver for C90TFS/FTFx Flash User’s Manual” document. For more information, please refer to Freescale website and search for “C90TFS” flash driver. Hope this will be useful for you. Best regards! /Carlos
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    以DMA方式通过UART发送数据应该是工程应用中很常用的一种方式了,尤其是在需要频繁发送数据或者数据包长度较大的场合,如果使用传统的UART查询或者中断方式发送和接收数据,对CPU资源的占用将是极大的浪费,带操作系统的应用还好些,如果是纯粹的前后台程序有时不能容忍的,所以DMA方式是很恰当的选择。 而本篇以Kinetis L系列为例介绍一下以DMA方式通过UART端口发送长数据包,当然不同于K系列复杂强大的eDMA功能,L系列的DMA模块配置起来还是比较简单的。 测试平台:IAR6.7 + KL26 FRDM 测试代码:FRDM-KL26Z_SC\FRDM-KL26Z_SC_Rev_1.0\klxx-sc-baremetal\build\iar\uart0_dma        其实KL26的官方sample code中是自带uart0_dma例程的,但是实现的功能只是将UART口接收到的每一个字节的数据通过DMA方式再发送出去(即环形缓冲),这样用来作为一个功能演示的demo是可以,但是往往我们需要的是将某缓冲区的数据以DMA方式发送出去或者将接收到的数据以DMA方式写到某缓冲区这样的功能,为此我们就需要在原有的例程上进行修改从而达到我们的应用目的,这里给出几点需要修改的地方,并做了相关注释(整个工程见最后附件): 1)定义待发送缓冲区: /* array to be sended */ uint8 testdata[]={"\nFreescale Kinetis KL26\n"}; 2)设置DMA源地址: #define DMA0_DESTINATION  0x4006A007    /* the memory adress of UART0_D register */ #define DMA0_SOURCE_ADDR  (uint32)testdata    /* define the source data array address */ 3) 在DMA0_init()函数中修改发送数据包的长度: DMA_SAR0 = DMA0_SOURCE_ADDR;    //Set source address to UART0_D REG DMA_DSR_BCR0 = DMA_DSR_BCR_BCR(sizeof(testdata));    //Set BCR to know how many bytes to transfer DMA_DCR0 &= ~(DMA_DCR_SSIZE_MASK | DMA_DCR_DSIZE_MASK);    //Clear source size and destination size fields 4)添加源地址自动加1功能,因为之前的环形缓冲方式只是单字节数据,所以不需要源地址递增,但是由于我们这次需要发送整个数据包,所以这里我们就需要将源地址递增功能打开,而具体递增1,2还是4则取决于发送数据的最小单位(8bit,16bit or 32bit): /* Set DMA as follows: Source size is 8-bit size Destination size is 8-bit size Cycle steal mode External requests are enabled source address increments 1 automatically */ DMA_DCR0 |= (DMA_DCR_SSIZE(1) | DMA_DCR_DSIZE(1) | DMA_DCR_CS_MASK | DMA_DCR_ERQ_MASK | DMA_DCR_EINT_MASK | DMA_DCR_SINC_MASK ); 5)配置DMAMUX通道为UART0 TX即发送通道(通道号为3),因为我们需要的是UART0_TX触发DMA传送: DMA_DAR0 = DMA0_DESTINATION;    //Set source address to UART0_D REG DMAMUX0_CHCFG0 = DMAMUX_CHCFG_SOURCE(3);    //Select UART0 TX as channel source DMAMUX0_CHCFG0 |= DMAMUX_CHCFG_ENBL_MASK;    //Enable the DMA MUX channel 6)在UART0_DMA_init()函数中修改UART0发送缓冲区为空时即触发DMA发送: void UART0_DMA_init(void) { UART0_C2 &= ~(UART0_C2_TE_MASK | UART0_C2_RE_MASK);  //Disable UART0 UART0_C5 |= UART0_C5_TDMAE_MASK;                      // Turn on DMA request(Transmit) for UART0 UART0_C2 |= (UART0_C2_TE_MASK | UART0_C2_RE_MASK);  //Enable UART0 } 7)在DMA发送完成中断服务函数中禁掉DMA通道,实现单次发送,即每个数据包发送完成之后即停止发送,否则不禁掉的话会一直触发DMA发送,造成串口堵塞: void DMA0_IRQHandler(void) {  /* Create pointer & variable for reading DMA_DSR register */ volatile uint32_t* dma_dsr_bcr0_reg = &DMA_DSR_BCR0; uint32_t dma_dsr_bcr0_val = *dma_dsr_bcr0_reg; if (((dma_dsr_bcr0_val & DMA_DSR_BCR_DONE_MASK) == DMA_DSR_BCR_DONE_MASK)      | ((dma_dsr_bcr0_val & DMA_DSR_BCR_BES_MASK) == DMA_DSR_BCR_BES_MASK)      | ((dma_dsr_bcr0_val & DMA_DSR_BCR_BED_MASK) == DMA_DSR_BCR_BED_MASK)      | ((dma_dsr_bcr0_val & DMA_DSR_BCR_CE_MASK) == DMA_DSR_BCR_CE_MASK)) { DMA_DSR_BCR0 |= DMA_DSR_BCR_DONE_MASK;                //Clear Done bit DMA_DSR_BCR0 = DMA_DSR_BCR_BCR(sizeof(testdata));      //Reset BCR dma0_done = 1; } /* once the array complete the transfer, then disable the DMA channel.*/ DMAMUX0_CHCFG0 &= ~DMAMUX_CHCFG_ENBL_MASK; }        将上述代码做完相应修改即可实现单次将内存缓冲区数据以DMA方式通过UART0发送出去,效果如下。此外,如果想周期性触发或者条件性触发,则只需再相应位置添加“ DMAMUX0_CHCFG0 |= DMAMUX_CHCFG_ENBL_MASK; ”这句代码即可打开通道,然后立即会触发UART0_TX发送数据,然后待数据包发送完之后再次停止等待下次使能。 另外,关于DMA的传输速度的话,因为其独立占用一条自己的总线,其搬运时钟为系统时钟(即coreclock/Systemclock),相比于总线上的传输速度,本例程中整个数据包的发送时间主要是取决于UART串口的波特率*数据包长度。 附件为修改好后的完整工程:
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Introduction With the growth of the Internet of Things (IoT), more and more applications are incorporating the use of sensors while also requiring power efficiency and increased performance.  A popular interface for these sensors is the I2C protocol. The I2C bus is a great protocol that is a true multi-master protocol and allows for each bus to contain many devices.  As the performance demand of the application grows, so will the speed of the I2C bus as it will be necessary to get more data from the sensors and/or at a faster rate.  Many applications may already have a need to operate an I2C bus at 400 kHz or more.  Higher data rates means the MCU core will need to spend more time servicing the I2C transactions.  The DMA module is one good way to free up the core in order to let it tend to other aspects of the application.  This can add much needed or much desired performance to applications.  Especially applications that may be using small, power efficient, single core MCUs. It may seem like an easy, straight-forward task to add I2C reads from a sensor to an application.  However I2C is a time sensitive protocol and consequently, so is the I2C peripherals on MCUs.  It is important to understand the time requirements and how to overcome them. The recommended approach is to use DMA to transfer the received I2C data to the desired buffer in your application software.  This document is going to outline how to setup your DMA and provide an example of how to do this for a KW40 device using the Kinetis SDK version 1.3.  The KW40 is being targeted because this is a small, power efficient MCU that incorporates a radio for your wireless applications and as such, it is likely that your application could need this DMA approach.  The KSDK version 1.3 is being targeted because this version of the SDK does not currently support DMA transactions for the I2C peripheral. Understanding the Kinetis I2C peripheral module Before getting into the specifics of creating a DMA enabled I2C driver, it is important to understand some basics of the Kinetis I2C peripheral module.  This module handles a lot of the low-level timing.  However the I2C registers must be serviced in a timely manner to operate correctly.  Take the case of a master reading data from a typical I2C sensor as shown in the diagram below. In the diagram above, the red lines indicate points in the transaction where software or DMA needs to interact with the I2C peripheral to ensure the transaction happens correctly.  To begin a transaction the core must change the MST bit which puts a start bit on the bus (marked by symbol ST).  Immediately following this, the core should then also write the target slave's address (Device Address) including the read/write bit (R/W).  Once this transaction is complete, the I2C will issue an interrupt and then the core should write the register address to be read from. Upon completion of that being put on the bus, the I2C will issue another interrupt and the master should then put a repeated start (SR) on the bus as well as the slave's address again.  Now the slave will send data to the master (once the master begins the transaction by issuing a dummy read of the I2C data register).  In the standard configuration, the I2C peripheral will automatically send the NAK or AK depending on the configuration of the TXAK bit in the I2C peripheral.  Because of this automation, it is important that this bit be handled properly and is configured one frame in advance. Furthermore, to ensure that the NAK bit is sent at the appropriate time, the TXAK bit must be set when the second to last byte is received.  The timing of this configuration change is very important to ensuring that the transaction happens properly. This document will describe how to use DMA to receive the data.  The DMA will be configured before the transaction begins and will be used to receive the data from the slave.  The document will also discuss options to handle proper NAK'ing of the data to end the transaction. Writing a DMA I2C master receive function The first step in adding DMA capability to your SDK driver is to create a new receive function with an appropriate name.  For this example, the newly created receive function is named I2C_DRV_MasterReceiveDataDMA.  To create this function, the I2C_DRV_MasterReceive function (which is called for both blocking and non-blocking) was copied and then modified by removing the blocking capability of the function. Then in this function, after the dummy read of the IIC data register that triggers the reception of data, the DMA enable bit of the I2C control register is written. /*FUNCTION********************************************************************** * * Function Name : I2C_DRV_MasterReceiveDataDMA * Description   : Performs a non-blocking receive transaction on the I2C bus *                 utilizing DMA to receive the data. * *END**************************************************************************/ i2c_status_t I2C_DRV_MasterReceiveDataDMA(uint32_t instance,                                                const i2c_device_t * device,                                                const uint8_t * cmdBuff,                                                uint32_t cmdSize,                                                uint8_t * rxBuff,                                                uint32_t rxSize,                                                uint32_t timeout_ms) {     assert(instance < I2C_INSTANCE_COUNT);     assert(rxBuff);       I2C_Type * base = g_i2cBase[instance];     i2c_master_state_t * master = (i2c_master_state_t *)g_i2cStatePtr[instance];             /* Return if current instance is used */     OSA_EnterCritical(kCriticalDisableInt);         if (!master->i2cIdle)     {         OSA_ExitCritical(kCriticalDisableInt);         return kStatus_I2C_Busy;     }         master->rxBuff = rxBuff;     master->rxSize = rxSize;     master->txBuff = NULL;     master->txSize = 0;     master->status = kStatus_I2C_Success;     master->i2cIdle = false;     master->isBlocking = true;     OSA_ExitCritical(kCriticalDisableInt);             while(I2C_HAL_GetStatusFlag(base, kI2CBusBusy));     I2C_DRV_MasterSetBaudRate(instance, device);         /* Set direction to send for sending of address. */     I2C_HAL_SetDirMode(base, kI2CSend);       /* Enable i2c interrupt.*/     I2C_HAL_ClearInt(base);     I2C_HAL_SetIntCmd(base, true);       /* Generate start signal. */     I2C_HAL_SendStart(base);       /* Send out slave address. */     I2C_DRV_SendAddress(instance, device, cmdBuff, cmdSize, kI2CReceive, timeout_ms);       /* Start to receive data. */     if (master->status == kStatus_I2C_Success)     {         /* Change direction to receive. */         I2C_HAL_SetDirMode(base, kI2CReceive);                 /* Send NAK if only one byte to read. */         if (rxSize == 0x1U)         {         I2C_HAL_SendNak(base);         }         else         {         I2C_HAL_SendAck(base);         }                 /* Dummy read to trigger receive of next byte in interrupt. */         I2C_HAL_ReadByte(base);                 /* Now set the DMA bit to let the DMA take over the reception. */         I2C_C1_REG(I2C1) |= I2C_C1_DMAEN_MASK;                 /* Don't wait for the transfer to finish. Exit immediately*/     }     else if (master->status == kStatus_I2C_Timeout)     {         /* Disable interrupt. */         I2C_HAL_SetIntCmd(base, false);                 if (I2C_HAL_GetStatusFlag(base, kI2CBusBusy))         {         /* Generate stop signal. */         I2C_HAL_SendStop(base);         }                 /* Indicate I2C bus is idle. */         master->i2cIdle = true;     }         return master->status; } After writing the DMA driver, a DMA specific transfer complete function must be implemented. This is needed in order for the application software to signal to the driver structures that the transfer has been completed and the bus is now idle. In addition, the DMA enable bit needs to be cleared in order for other driver functions to be able to properly use the IIC peripheral. void I2C_DRV_CompleteTransferDMA(uint32_t instance) {     assert(instance < I2C_INSTANCE_COUNT);     I2C_Type * base = g_i2cBase[instance];     i2c_master_state_t * master = (i2c_master_state_t *)g_i2cStatePtr[instance];         I2C_C1_REG(base) &= ~(I2C_C1_DMAEN_MASK | I2C_C1_TX_MASK);     I2C_C1_REG(base) &= ~I2C_C1_MST_MASK;;        /* Indicate I2C bus is idle. */     master->i2cIdle = true; } DMA Configuration Next, the application layer needs a function to configure the DMA properly, and a DMA callback is needed to properly service the DMA interrupt that will be used as well as post a semaphore. But before diving into the specifics of that, it is important to discuss the overall strategy of using the DMA in this particular application. After every transaction, the data register must be serviced to ensure that all of the necessary data is received.  One DMA channel can easily be assigned to service this activity.  After the reception of the second to last data byte, the TXAK bit must be written with a '1' to ensure that the NAK is put on the bus at the appropriate time. This is a little trickier to do.  There are three options: A second dedicated DMA channel can be linked to write the I2C_C1 register every time the I2C_D register is serviced.  This option will require a second array to hold the appropriate values to be written to the I2C_C1 register.  The following figure illustrates this process. The second DMA channel can be linked to write the I2C_C1 register after the second to last data byte has been received.  This option would require that the primary DMA channel be set to receive two data bytes less than the total number of desired data bytes.  The primary DMA channel would also need to be re-configured to receive the last two bytes (or the application software would need to handle this).  However this could be a desirable programming path for applications that are memory constrained as it reduces the amount of memory necessary for your application. The primary DMA channel can be set to receive two data bytes less than the total number of desired data bytes and the core (application software) can handle the reception of the last two bytes.  This would be a desirable option for those looking for a simpler solution but has the drawback that in a system where the core is already handling many other tasks, there may still be issues with writing the TXAK bit on time. This example will focus on option number 1, as this is the simplest, fully automatic solution.  It could also easily be modified to fit the second option as the programmer would simply need to change the number of bytes to receive by the primary DMA and add some reconfiguration information in the interrupt to service the primary DMA channel. DMA Channel #1 The first DMA channel is configured to perform 8-bit  transfers from the I2C data register (I2C_D) to the buffer to hold the desired data.  This channel should transfer the number of desired bytes minus one.  The final byte will be received by the core.  Other DMA configuration bits that are important to set are the cycle steal bit, disable request bit, peripheral request bit (ERQ), interrupt on completion of transfer (EINT), and destination increment (DINC).  It also important to configure the link channel control to perform a link to channel LCH1 after each cycle-steal transfer and LCH1 should be configured for the channel that will transfer from memory to the I2C control register (I2C_C1).  The first DMA channel is configured as shown below. // Set Source Address (this is the UART0_D register       DMA_SAR0 = (uint32_t)&I2C_D_REG(base);             // Set BCR to know how many bytes to transfer       // Need to set to desired size minus 1 because the last will be manually       // read.        DMA_DSR_BCR0 = DMA_DSR_BCR_BCR(destArraySize - 1);             // Clear Source size and Destination size fields.        DMA_DCR0 &= ~(DMA_DCR_SSIZE_MASK                     | DMA_DCR_DSIZE_MASK                     );       // Set DMA as follows:       //     Source size is byte size       //     Destination size is byte size       //     D_REQ cleared automatically by hardware       //     Destination address will be incremented after each transfer       //     Cycle Steal mode       //     External Requests are enabled       //     Interrupts are enabled       //     Asynchronous DMA requests are enabled.       //     Linking to channel LCH1 after each cycle steal transfer       //     Set LCH1 to DMA CH 1.        DMA_DCR0 |= (DMA_DCR_SSIZE(1)             // 1 = 8-bit transfers                    | DMA_DCR_DSIZE(1)           // 1 = 8-bit transfers                    | DMA_DCR_D_REQ_MASK                    | DMA_DCR_DINC_MASK                    | DMA_DCR_CS_MASK                    | DMA_DCR_ERQ_MASK                    | DMA_DCR_EINT_MASK                    | DMA_DCR_EADREQ_MASK                    | DMA_DCR_LINKCC(2)          // Link to LCH1 after each cycle-steal transfer                    | DMA_DCR_LCH1(1)            // Link to DMA CH1                    );       // Set destination address       DMA_DAR0 = (uint32_t)destArray; DMA Channel #2 The second DMA channel, which is the linked channel, should be configured to perform 8-bit transfers that transfer data from an array in memory (titled ack_nak_array in this example) to the I2C control register (I2C_C1).  This channel should also disables requests upon completion of the entire transfer, and enable the cycle-steal mode.  In this channel, the source should be incremented (as opposed to the destination as in the first channel). This channel is configured as shown below: // Set Source Address (this is the UART0_D register       DMA_SAR1 = (uint32_t)ack_nak_array;             // Set BCR to know how many bytes to transfer       // Need to set to desired size minus 1 because the last will be manually       // read.       DMA_DSR_BCR1 = DMA_DSR_BCR_BCR(destArraySize - 1);             // Clear Source size and Destination size fields.        DMA_DCR1 &= ~(DMA_DCR_SSIZE_MASK                     | DMA_DCR_DSIZE_MASK                     );             // Set DMA as follows:       //     Source size is byte size       //     Destination size is byte size       //     D_REQ cleared automatically by hardware       //     Destination address will be incremented after each transfer       //     Cycle Steal mode       //     External Requests are disabled       //     Asynchronous DMA requests are enabled.       DMA_DCR1 |= (DMA_DCR_SSIZE(1)             // 1 = 8-bit transfers                    | DMA_DCR_DSIZE(1)           // 1 = 8-bit transfers                    | DMA_DCR_D_REQ_MASK                    | DMA_DCR_SINC_MASK                    | DMA_DCR_CS_MASK                    | DMA_DCR_EADREQ_MASK                    );             // Set destination address       DMA_DAR1 = (uint32_t)&I2C_C1_REG(base); Once the DMA channels are initialized, the only action left is to configure the interrupts, enable the channel in the DMA MUX, and create the semaphore if it has not already been created.  This is done as shown below. //Need to enable the DMA IRQ       NVIC_EnableIRQ(DMA0_IRQn);       //////////////////////////////////////////////////////////////////////////       // MUX configuration       // Enables the DMA channel and select the DMA Channel Source        DMAMUX0_CHCFG0 = DMAMUX_CHCFG_SOURCE(BOARD_I2C_DMAMUX_CHN); //DMAMUX_CHCFG_ENBL_MASK|DMAMUX_CHCFG_SOURCE(0x31); //0xb1;       DMAMUX0_CHCFG0 |= DMAMUX_CHCFG_ENBL_MASK;             /* Create semaphore */       if(semDmaReady == NULL){         semDmaReady = OSA_EXT_SemaphoreCreate(0);       } Finally, the DMA initialization function also initializes the ack_nak_array.  This is only necessary when implementing the first DMA strategy.  The second DMA strategy would only need to write a single value at the correct time.  The array initialization for strategy #1 is shown below.  Note that the values written to the array are 0xA1 plus the appropriate value of the TXAK bit.  By writing 0xA1, it is ensured that the I2C module will be enabled in master mode with the DMA enable bit set. // Initialize Ack/Nak array       // Need to initialize the Ack/Nak buffer first       for( j=0; j < destArraySize; j++)       {           if(j >= (destArraySize - 2))           {               ack_nak_array[j] = 0xA1 | I2C_C1_TXAK_MASK;           }           else           {               ack_nak_array[j] = 0xA1 & (~I2C_C1_TXAK_MASK);           }       } DMA Interrupt Handler Now a DMA interrupt handler is required.  A minimum of overhead will be required for this example as the interrupt handler simply needs to service the DONE bit and post the semaphore created in the initialization.  The DMA interrupt handler is as follows: void DMA0_IRQHandler(void) {     // Clear pending errors or the done bit     if (((DMA_DSR_BCR0 & DMA_DSR_BCR_DONE_MASK) == DMA_DSR_BCR_DONE_MASK)         | ((DMA_DSR_BCR0 & DMA_DSR_BCR_BES_MASK) == DMA_DSR_BCR_BES_MASK)         | ((DMA_DSR_BCR0 & DMA_DSR_BCR_BED_MASK) == DMA_DSR_BCR_BED_MASK)         | ((DMA_DSR_BCR0 & DMA_DSR_BCR_CE_MASK) == DMA_DSR_BCR_CE_MASK))     {         // Clear the Done MASK and set semaphore, dmaDone         DMA_DSR_BCR0 |= DMA_DSR_BCR_DONE_MASK;         //dmaDone = 1;         OSA_SemaphorePost(semDmaReady);     } } Using your newly written driver function Once all of these items have been taken care of, it is now time for the application to use the functions. It is expected that the DMA will be initialized before calling the DMA receive function.  After the first call, the DMA can be re-initialized every time or could simply be reset with the start address of the arrays and byte counter (this is the minimum of actions that must be performed).  Then the application should ensure that the transaction happened successfully.   Upon a successful call to the I2C_DRV_MasterReceiveDataDMA function, the application should wait for the semaphore to be posted.  Once the semaphore posts, the application software should wait for the Transfer Complete flag to become set.  This ensures that the application does not try to put a STOP signal on the bus before the NAK has been physically put on the bus.  If the STOP signal is attempted out of sequence, the I2C module could be put in an erroneous state and the STOP signal may not be sent.  Next, the I2C_DRV_CompleteTransferDMA function should be called to send the STOP signal and to signal to the driver structures that the bus is idle.  At this point, the I2C transaction is now fully complete and there is still one data byte that hasn't been transferred to the receive buffer.  It is the application's responsibility to perform one last read of the Data register to receive the last data byte of the transaction. /* Now initialize the DMA */    dma_init(BOARD_I2C_INSTANCE, Buffer, ack_nak_buffer, FXOS8700CQ_READ_LEN); //Init DMAMUX       returnValue = I2C_DRV_MasterReceiveDataDMA(BOARD_I2C_INSTANCE, &slave,                                                   cmdBuff, 1, Buffer, FXOS8700CQ_READ_LEN, 1000); if (returnValue != kStatus_I2C_Success)    {        return (kStatus_I2C_Fail);    } /* Wait for the DMA transaction to complete */    OSA_SemaphoreWait(semDmaReady, OSA_WAIT_FOREVER);       /* Need to wait for the transfer to complete */ for(temp=0; temp<250; temp++)     {         if(I2C_HAL_GetStatusFlag(base, kI2CTransferComplete))         {             break;         }     }       /* Now complete the transfer; this includes sending the I2C STOP signal and       clearing the DMA enable bit */    I2C_DRV_CompleteTransferDMA(BOARD_I2C_INSTANCE);       // Once the Transfer is complete, there is still one byte sitting in the Data    // register.      Buffer[11] = I2C_D_REG(g_i2cBase[BOARD_I2C_INSTANCE]); Conclusion To summarize, as consumers demand more and more power efficient technology with more and more functionality, MCU product developers need to cram more functionality in small power efficient MCUs.  Relying on DMA for basic data transfers is one good way to improve performance of smaller power efficient MCUs with a single core. This can be particularly useful in applications where an MCU needs to pull information from and I2C sensor.  To do this, there are three methods of implementing an I2C master receive function in your SDK 1.3 based application. Use two DMA channels.  The first to transfer from the I2C Data register to the destination array.  A second dedicated DMA channel can be linked to write the I2C_C1 register every time the I2C_D register is serviced. Use two DMA channels.  The first to transfer from the I2C Data register to the destination array. The second DMA channel can be linked to write the I2C_C1 register only after the second to last data byte has been received. Use a single DMA channel can be set to receive two data bytes less than the total number of desired data bytes and the core (application software) can handle the reception of the last two bytes. The recommendation of this document is to implement the first or second option as these are fully automatic options requiring the least intervention by the core.
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With the merger of NXP and Freescale, the NXP USB VID/PID program, which was previously deployed on LPC Microcontrollers, has been extended to Kinetis Microcontrollers and i.MX Application Processors. The USB VID/PID Program enables NXP customers without USB-IF membership to obtain free PIDs under the NXP VID. What is USB VID/PID Program? The NXP USB VID program will allow users to apply for the NXP VID and get up to 3 FREE PIDs. For more details, please review the application form and associated FAQ below. Steps to apply for the NXP USB VID/PID Program Step 1: Fill the application form with all relevant details including contact information. Step 2: NXP will review the application and if approved, will issue you the PIDs within 4 weeks FAQ for the USB VID/PID Program Can I use this VID for any microcontroller in the NXP portfolio? >> No. This program is intended only for the Cortex M based series of LPC Microcontrollers and Kinetis Microcontrollers, and Cortex A based series of i.MX Application Processors. What are the benefits of using the NXP VID/PID Program? >> USB-IF membership not required >> Useful for low volume production runs that do not exceed 10,000 units >> Quick time to market Can I use the NXP VID and issued PID/s for USB certification? >> You may submit a product using the NXP VID and issued PID/s for compliance testing to qualify to use the Certified USB logo in conjunction with the product, but you must provide written authorization to use the VID from NXP at the time of registration of your product for USB certification. Additionally, subject to prior approval by USB-IF, you can use the NXP VID and assigned PID/s for the purpose of verifying or enabling interoperability. What are the drawbacks of using the NXP VID/PID program? >> Production run cannot exceed 10,000 units. See NXP VID application for more details. >> Up to 3 PIDs can be issued from NXP per customer. If more than 3 PIDs are needed, you have to get your own VID from usb.org: http://www.usb.org/developers/vendor/ >> The USB integrators list is only visible to people who are members of USB-IF. NXP has full control on selecting which products will be visible on the USB integrators list. How do I get the VID if I don't use NXP’s VID? >> You can get your own VID from usb.org. Please visit http://www.usb.org/developers/vendor/ Do I also get the license to use the USB-IF’s trademarked and licensed logo if I use the NXP VID? >> No. No other privileges are provided other than those listed in the NXP legal agreement. If you wish to use USB-IF’s trademarked and licensed USB logo, please follow the below steps:                 1. The company must be a USB vendor (i.e. obtain a USB vendor ID).                 2. The company must execute the USB-IF Trademark License Agreement.                 3. The product bearing the logo must successfully pass USB-IF Compliance Testing and appear on the Integrators List under that company’s name. Can I submit my product for compliance testing using the NXP VID and assigned PIDs? >> Yes, you would be able to submit your products for USB-IF certification by using the NXP VID and assigned PID. However, if the product passes the compliance test and gets certified, it will be listed under “NXP Semiconductors” in the Integrators list. Also, you will not have access to use any of the USB-IF trademarked and licensed USB logos. How long does it take to obtain the PID from NXP? >> It can take up to 4 weeks to get the PIDs from NXP once the application is submitted. Are there any restrictions on the types of devices that can be developed using the NXP issued PIDs? >> This service requireds the USB microcontroller to be NXP products. Can I choose/request for a specific PID for my application? >> No. NXP will not be able to accommodate such requests.
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The FRDM-KL25Z is an ultra-low-cost development platform enabled by Kinetis L Series KL1 and KL2 MCUs families built on ARM® Cortex™-M0+ processor. Features include easy access to MCU I/O, battery-ready, low-power operation, a standard-based form factor with expansion board options and a built-in debug interface for flash programming and run-control. The FRDM-KL25Z is supported by a range of Freescale and third-party development software. Features MKL25Z128VLK4 MCU – 48 MHz, 128 KB flash, 16 KB SRAM, USB OTG (FS), 80LQFP Capacitive touch “slider,” MMA8451Q accelerometer, tri-color LED Easy access to MCU I/O Sophisticated OpenSDA debug interface Mass storage device flash programming interface (default) – no tool installation required to evaluate demo apps P&E Multilink interface provides run-control debugging and compatibility with IDE tools Open-source data logging application provides an example for customer, partner and enthusiast development on the OpenSDA circuit Take a look at these application notes: USB DFU boot loader for MCUs Developer’s Serial Bootloader. Low Cost Universal Motor Drive Using Kinetis L family . Writing your First MQXLite Application Learn more...
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  Hello Freedom community users Few weeks before, I produced for the Element14 community a full video review of the FRDM-KL46Z including all the steps to program and debug your first project example. Video has a length of less than 13 min so your evaluation of the Kinetis KL46 should be really quick and easy http://www.element14.com/community/community/designcenter/kinetis_kl2_freedom_board/blog/2014/06/17/frdm-kl46z-full-review-and-getting-started-in-video Enjoy Greg
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As general introduction on thread https://community.freescale.com/docs/DOC-328302 , I did a smart LED application with GoKit and FRDM-KL02. In this design, FRDM-KL02 will communicate with GoKit by WIFI, and control LED flash. Code Structure Code Basic Introduction In this project structure, you need to do following items on code. ü Add your functions, such as UART, LED, motor driver code. ü Add function running functions in protocol.c ü Add functions order in main loop. You can find my main.c and protocol.c as attachment. In this document, I would like to detail introduce function MessageHandle() , void MessageHandle(void) {                 pro_headPart    tmp_headPart; //Common command package                 memset(&tmp_headPart, 0, sizeof(pro_headPart));                 if(get_one_package)                 {                                                                              get_one_package = 0;                                 memcpy(&tmp_headPart, uart_buf, sizeof(pro_headPart));                                                                 //CRC error, send back error command                                 if(CheckSum(uart_buf, uart_Count) != uart_buf[uart_Count-1])                                 {                                                 SendErrorCmd(ERROR_CHECKSUM, tmp_headPart.sn);                                                 return ;                                 }                                 So, you can see that only get_one_package=1, we can receive frame completely.                                 switch(tmp_headPart.cmd)                                 {                                                              case       CMD_GET_MCU_INFO:                                                                 CmdGetMcuInfo(tmp_headPart.sn);                                                                                                                                     break;                                                                   case CMD_SEND_HEARTBEAT:                                                                 SendCommonCmd(CMD_SEND_HEARTBEAT_ACK, tmp_headPart.sn);                                                                                 break;                                                 case CMD_REBOOT_MCU:                                                                 SendCommonCmd(CMD_REBOOT_MCU_ACK, tmp_headPart.sn);                                                 case       CMD_SEND_MCU_P0:                                                                 CmdSendMcuP0(uart_buf);                                                                 break;                                                 case       CMD_REPORT_MODULE_STATUS:                                                                 CmdReportModuleStatus(uart_buf);                                                                 break;                                                 default:                                                                 SendErrorCmd(ERROR_CMD, tmp_headPart.sn);                                                                 break;                                 }                              } } After that, you can do operations mentioned in thread https://community.freescale.com/docs/DOC-328302. You can see smart LED device and been found.
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Microgenios viabilizou a realização de videos de treinamentos de curta duração para ensinar os primeiros passos com o microcontrolador Kinetis L como parte do Road Show de Microcontroladores ARM cortex-M0+ (Kinetis L Freescale), projeto realizado em parceria pela a Freescale em 10 cidades espalhadas pelo Brasil. Veja os videos para iniciar seu projeto com Kinetis L : Neste vídeo aprenderemos o processo de download e instalação do CodeWarrior V10.3 e outros pacotes de softwares Freescale : http://www.youtube.com/watch?v=bjtsLHMImDY Neste vídeo aprenderemos o processo de atualização do CodeWarrior V10 (baseado no Eclipse) e conheceremos as pastas criadas na instalação: http://www.youtube.com/watch?v=Sslf0nF0Td8 Neste vídeo conheceremos a ferramenta de hardware Freedom Board da Freescale com microcontrolador ARM cortex-M0+; e entenderemos a utilização da interface de gravação e depuração OpenSDA: http://www.youtube.com/watch?v=jeuq7ErvTGQ Neste vídeo aprenderemos a criar nosso primeiro projeto com a Freedom Board (FRDM-KL25Z), que possui microcontrolador da família Kinetis L (núcleo ARM cortex-M0+) da Freescal; utilizaremos como ferramenta de software o CodeWarrior V10.3 e o Processor Expert : http://www.youtube.com/watch?v=sx2tpDBWDt8 Neste vídeo conheceremos a IDE cloud mbed, que possibilita desenvolvimento e aplicações diretamente no navegador: http://www.youtube.com/watch?v=N7qMvO_R6Sc Mais informações visite: http://www.microgenios.com.br/website/index.php/hands-on-freescale
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Many customers reported that their ADC function works on FRDM-KL27Z board but meet issue on their own board. We need to pay attention to the difference between the ADC reference voltages of different packages (on board MKL27Z64VLH4 is 64LQFP package). This tip introduce the ADC Reference Options on KL17/KL27 32/36pin package Part number involved: 32-pins 36-pins MKL17Z32VFM4 MKL17Z32VDA4 MKL17Z64VFM4 MKL17Z64VDA4 MKL27Z32VFM4 MKL27Z32VDA4 MKL27Z64VFM4 MKL27Z64VDA4 PTE30/VREF_OUT - connected as the primary reference option on 36-pin and below packages VDDA/VSSA - connected as the VALT reference option   ADCx_SC2[REFSEL] selects the voltage reference source used for conversions.   About the primary reference option : When on-chip 1.2V VREF is enabled, PTE30 pin must be used as VREF_OUT and has to be configured as an analog input, such as ADC0_SE23 (PORTE_PCR30[MUX] = 000). Notice: this pin needs to connect a capacitor to ground.   PTE30 can also be used as an external reference voltage input as long as PTE30 is configured as analog input and VREF module is disabled. It means you can connect external reference voltage to PTE30 pin and use it as ADC reference voltage. (For example 3.3V) KL17P64M48SF2RM     Kinetis KL17: 48MHz Cortex-M0+ 32-64KB Flash (32-64pin) (REV 4.1) KL27P64M48SF2RM     Kinetis KL27: 48MHz Cortex-M0+ 32-64KB Flash (32-64pin) (REV 4.1)
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The USB OTG module in Kinetis parts uses a Buffer Descriptor Table (BDT) in system memory to manage USB endpoint communications, the BDT is a a 512-byte buffer and there are 3 registers in USB module to contain the base address for it, and it must be 512-byte aligned otherwise there would be issue during transfer. In USB stack ver 4.1.1, some Kinetis old parts like K60N512, K20D72M have the demo project basked on CodeWarrior ARM compiler, and in khci_kinetis.c, bdt is defined as following: #define _BDT_RESERVED_SECTION_ #if (defined _BDT_RESERVED_SECTION_) #ifdef __CWCC__ #pragma define_section usb_bdt ".usb_bdt" RW __declspec (usb_bdt) uint_8_ptr bdt ; but since the base address is defined as below: #define BDT_BASE               ((uint_32*)(bdt)) so the bdt definition is not correct , and we have to change it as below: #define _BDT_RESERVED_SECTION_ #if (defined _BDT_RESERVED_SECTION_) #ifdef __CWCC__ #pragma define_section usb_bdt ".usb_bdt" RW __declspec (usb_bdt) uint_8 bdt[512]; //uint_8_ptr bdt ; and the definition for usb_dbt section can be found in MK20X256_flash.lcf. with above modification, we can make the demo of "msd_mfs_generic" work well as expected. Please kindly refer to the following result got from TWR-K20D72M. FAT demo Waiting for USB mass storage to be attached... Mass Storage Device Attached ****************************************************************************** * FATfs DEMO * * Configuration:  LNF Enabled, Code page =1258 * ****************************************************************************** ****************************************************************************** * DRIVER OPERATION * ****************************************************************************** 1. Demo function: f_mount   Initializing logical drive 0...   Initialization complete ----------------------------------------------------------------------------- 2. Demo functions:f_getfree, f_opendir, f_readdir getting drive 0 attributes............... Logical drive 0 attributes: FAT type = FAT16 Bytes/Cluster = 2048 Number of FATs = 2 Root DIR entries = 512 Sectors/FAT = 250 Number of clusters = 63858 FAT start (lba) = 36 DIR start (lba,clustor) = 536 Data start (lba) = 568 ... 127716 KB total disk space. 127624 KB available. ----------------------------------------------------------------------------- ****************************************************************************** * DRECTORY OPERATION * ****************************************************************************** 1. Demo functions:f_opendir, f_readdir Directory listing...     ----A 2014/04/16 17:25     32253  tek00000.png     ----A 2014/04/16 17:34     31451  tek00001.png     ----A 2014/07/04 14:57     20549  tek00002.png     DR--- 2010/12/25 23:30         0 DIRECT~1     D---- 2010/01/01 00:00         0 DIRECT~2 3    File(s),     84253 bytes total 2    Dir(s) ----------------------------------------------------------------------------- 2. Demo functions:f_mkdir 2.0. Create <Directory_1> 2.1. Create <Directory_2> 2.2. Create <Sub1> as a sub directory of <Directory_1> 2.3. Directory list Directory listing...     ----A 2014/04/16 17:25     32253  tek00000.png     ----A 2014/04/16 17:34     31451  tek00001.png     ----A 2014/07/04 14:57     20549  tek00002.png     DR--- 2010/12/25 23:30         0 DIRECT~1     D---- 2010/01/01 00:00         0 DIRECT~2 3    File(s),     84253 bytes total 2    Dir(s) ----------------------------------------------------------------------------- 3. Demo functions:f_getcwd, f_chdir 3.0. Get the current directory     CWD: 0:/ 3.1. Change current directory to <Directory_1> 3.2. Directory listing Directory listing...     D---- 2010/01/01 00:00         0  .     D---- 2010/01/01 00:00         0  ..     D---- 2010/01/01 00:00         0  sub1 0    File(s),         0 bytes total 3    Dir(s) 3.3. Get the current directory     CWD: 0:/Directory_1 ----------------------------------------------------------------------------- 4. Demo functions:f_stat(File status), f_chmod, f_utime 4.1. Get directory information of <Directory_1>     DR--- 2010/12/25 23:30         0 Directory_1 4.2  Change the timestamp of Directory_1 to 12.25.2010: 23h 30' 20 4.3. Set Read Only Attribute to Directory_1 4.4. Get directory information (Directory_1)     DR--- 2010/12/25 23:30         0 Directory_1 ----------------------------------------------------------------------------- 5. Demo functions:f_rename Rename <sub1> to <sub1_renamed> and move it to <Directory_2> Directory listing...     D---- 2010/01/01 00:00         0  .     D---- 2010/01/01 00:00         0  ..     D---A 2010/01/01 00:00         0 SUB1_R~1 0    File(s),         0 bytes total 3    Dir(s) ----------------------------------------------------------------------------- 6. Demo functions:f_unlink Delete Directory_1/sub1_renamed Directory listing...     D---- 2010/01/01 00:00         0  .     D---- 2010/01/01 00:00         0  .. 0    File(s),         0 bytes total 2    Dir(s) ****************************************************************************** * FILE OPERATION * ****************************************************************************** 1. Demo functions:f_open,f_write, f_printf, f_putc, f_puts, fclose 1.0. Create new file <New_File_1> (f_open)     File size =    0 1.1. Write data to <New_File_1>(f_write) 1.2. Flush cached data     File size =   52 1.3. Write data to <New_File_1> (f_printf) 1.4. Flush cached data     File size =  103 1.5. Write data to <New_File_1> (f_puts) 1.6. Flush cached data     File size =  152 1.7. Write data to <New_File_1> uses f_putc function 1.8. Flush cached data     File size =  199 1.9. Close file <New_File_1> ----------------------------------------------------------------------------- 2. Demo functions:f_open,f_read, f_seek, f_gets, f_close 2.0. Open <New_File_1> to read (f_open) 2.1. Get a string from file (f_gets)     Line 1: Write data to  file uses f_write function 2.2. Get the rest of file content (f_read)     Line 2: Write data to file uses f_printf function Line 3: Write data to file uses f_puts function Line 4: Write data to file uses f_putc functionûöF¬  â•:7Rz}™ yzjw8¸×áÀ—»ÃЭ¹òÍ­ ä ‹ Hïk¨Wã½c'     ²7këÞÑ%VrC×»Ô¼ÒSÈÑèR+NjD¡¾òû>ú3‰SËþo^ÎI Pë±ñ‰þ/Directory_1 [1] 2.3. Close file (f_close) ----------------------------------------------------------------------------- 3. Demo functions:f_stat, f_utime, f_chmod 3.1. Get  information of <New_File_1> file (f_stat)     ----A 2010/01/01 00:00       199  New_File_1.dat 3.2  Change the timestamp of Directory_1 to 12.25.2010: 23h 30' 20 (f_utime) 3.3. Set Read Only Attribute to <New_File_1> (f_chmod) 3.4. Get directory information of <New_File_1> (f_stat)     -R--A 2010/12/25 23:30       199  New_File_1.dat 3.5. Clear Read Only Attribute of <New_File_1> (f_chmod) 3.6. Get directory information of <New_File_1>     ----A 2010/12/25 23:30       199  New_File_1.dat ----------------------------------------------------------------------------- 4. Demo functions:f_ulink Rename <New_File_1.dat> to  <File_Renamed.txt> Directory listing...     D---- 2010/01/01 00:00         0  .     D---- 2010/01/01 00:00         0  ..     ----A 2010/12/25 23:30       199  FILE_R~1.TXT 1    File(s),       199 bytes total 2    Dir(s) ----------------------------------------------------------------------------- 5. Demo functions:f_truncate Truncate file <File_Renamed.txt> 5.0. Open <File_Renamed.txt> to write 5.1. Seek file pointer     Current file pointer:    0     File pointer after seeking:  102 5.2. Truncate file     File size =  102 5.3. Close file ----------------------------------------------------------------------------- 6. Demo functions:f_forward 6.0. Open <File_Renamed.txt> to read 6.1. Forward file to terminal Line 1: Write data to  file uses f_write function Line 2: Write data to file uses f_printf function 6.2. Close file ----------------------------------------------------------------------------- 7. Demo functions:f_ulink Delete <File_Renamed.txt> Directory listing...     D---- 2010/01/01 00:00         0  .     D---- 2010/01/01 00:00         0  .. 0    File(s),         0 bytes total 2    Dir(s) *------------------------------ DEMO COMPLETED    ------------------------ * ******************************************************************************
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There is a popular WIFI platform called “GoKit” in China. This testing kit can be use to do some customized application. Not only WIFI communication, kit also support other functions. You can find interfaces listed as below. GoKit Interfaces: I try to use FRDM-KL02 to communicate with this kit to do a WIFI communication application. Board connection as below. This platform has two running mode. One is AirLink mode, and another is normal running mode. AirLink mode is used to WIFI communication or pair. Go to AirLink mode steps: Power on FRDM-KL02 Long press key1 to reset WIFI module. Wait until RED led on. Short press Key2 to go into configuration mode, wait until RED led flash on WIFI module. Open demo APP, select “adding device”, input SSID password. Waiting for configuration finish. Command Format HOF: 2bytes, value 0xFFFF Length: 2bytes Cmd:1byte SN:1byte Flags:2bytes DATA: Xbytes Checksum:1byte WIFI acquire device information MCU inform WIFI into configure mode MCU reset WIFI WIFI inform MCU status WIFI ask for reset Illegal command For detail code, I will post another thread for your reference.
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When using ADCs it is not enough to just configure the module, add a clock signal, apply the Nyquist criteria and hope for the best, because normally that is just not enough. Even if we use the best software configuration, sampling rate, conversion time, etc; we might end up with noisy conversions, and worst of all a low ENOB figure which sums up in a lousy, low resolution ADC application. To complement the software end you need to follow some basic hardware design rules, some of them might seem logical, other might even weird or excessive however they are the key to a successful conversion, I took the time to compile a short list of effective design best practices trying to cover the basics of ADC design. If you think I missed something feel free to comment and ask for more information. Ground Isolation Because ground is the power return for all digital circuits and analog circuits, one of the most basic design philosophies is to isolate digital and analog grounds. If the grounds are not isolated, the return from the analog circuitry will flow through the analog ground impedance and the digital ground current will flow through the analog ground, usually the digital ground current is typically much greater than the analog ground current.  As the frequency of digital circuits increases, the noise generated on the ground increases dramatically. CMOS logic families are of the saturating type; this means the logic transitions cause large transient currents on the power supply and ground. CMOS outputs connect the power to ground through a low impedance channel during the logic transitions. Digital logic waveforms are rectangular waves which imply many higher frequency harmonic components are induced by high speed transmission lines and clock signals.                              Figure 1: Typical mixed signal circuit grou nding                              Figure 2: Isolated mixed signal circuit grounding Inductive decoupling Another potential problem is the coupling of signal from one circuit to another via mutual inductance and it does not matter if you think the signals are too weak to have a real effect, the amount of coupling will depend on the strength of the interference, the mutual inductance, the area enclosed by the signal loop (which is basically an antenna), and the frequency. It will also depend primarily on the physical proximity of the loops, as well as the permeability of the material. This inductive coupling is also known as crosstalk in data lines.                               Figure 3: Coupling induced noise It may seem logical to use a single trace as the return path for the two sources (dotted lines). However, this would cause the return currents for both signals to flow through the same impedance, in addition; it will maximize the area of the interference loops and increase the mutual inductance by moving the loops close together. This will increase the mutual noise inductance and the coupling between the circuits. Routing the traces in the manner shown below minimizes the area enclosed by the loops and separates the return paths, thus separating the circuits and, in turn, minimizing the mutual noise inductance.                               Figure 4: Inductance decoupling layout Power supply decoupling The idea after power decoupling is to create a low noise environment for the analog circuitry to operate. In any given circuit the power supply pin is really in series with the output, therefore, any high frequency energy on the power line will couple to the output directly, which makes it necessary to keep this high frequency energy from entering the analog circuitry. This is done by using a small capacitor to short the high frequency signals away from the chip to the circuit’s ground line. A disadvantage of high frequency decoupling is it makes a circuit more prone to low frequency noise however it is easily solved by adding a larger capacitor. Optimal power supply decoupling A large electrolytic capacitor (10 μF – 100 μF) no more than 2 in. away from the chip. A small capacitor (0.01 μF – 0.1 μF) as close to the power pins of the chip as possible. A small ferrite bead in series with the supply pin (Optional).                               Figure 5: Power supply decoupling layout Treat signal lines as transmission lines Although signal coupling can be minimized it cannot be avoided, the best approach to effectively counteract its effects on signal lines is to channel it into a conductor of our choice, in this case the circuit’s ground is the best choice to channel the effects of inductive coupling; we can accomplish this by routing ground lines along signal lines as close as manufacturing capabilities allow. An very effective way to accomplish this is routing signals in triplets, these works for both digital and analog signals.The advantages of doing so are an improved immunity not only to inductive coupling but also immunity to external noise. Optimal routing: Routing in “triplets” (S-G-S) provide good signal coupling with relatively low impact on routing density Ground trace needs to be connected to the ground pins on the source and destination devices for the signal traces Spacing should be as close as manufacturing will allow                               Figure 6: Transmission line routing Signal acquisition circuit To improve noise immunity an external RC acquisition circuit can be added to the ADC input, it consists of a resistor in series with the ADC input and a capacitor going from the input to the circuit’s ground as the figure below shows:                                                             Figur e 7 : ADC with an external acquisition circuit The external RC circuit values depend on the internal characteristics and configuration of the ADC you use, such as the availability of an internal gain amplifier or the ADC’s architecture; the equation and circuit shown here represents a simplified form of ADC used in Freescale devices. The equivalent sampling resistance RSH is represented by total serial resistance connected between sampling capacitance and analog input pin (sampling switch, multiplexor switches etc.). The sampling capacitance CSH is represented by total parallel capacitance. For example in a case of Freescale SAR ADC equivalent sampling capacitance contains bank of capacitances. The equation shown how to calculate the value of the input resistor based on the values of both the input and sample and hold circuit. It must be noted the mentioned figures could have an alternate designation in any given datasheet; the ones mentioned here are specific to Kinetis devices: TAQ=      Acquisition time (.5/ADC clock) CIN=        Input capacitance (33pF min) CSH=       Sample & Hold circuit capacitance ( CDAIN in datasheet) VIN=        Input voltage level VCSH0= Initial voltage across S&H circuit (0V) VSFR=     Full scale voltage (VDDA) N=           bit resolution Note:  Special care must be taken when performing the calculation since a deviation from the correct values will result in a significant conversion error due to signal distortion.
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Hello Freedom users I have created another full board review this time for the FRDM-KL05Z always including clear instructions to program and debug your first project. I'm still working on the video version (looking for a better accent :smileyconfused:), but the commands illustrated by screen captures should be easy to follow. Freescale Freedom development platform: [FRDM-K... | element14 Enjoy Greg
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