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Kinetis Microcontrollers Knowledge Base

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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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Hello Kinetis community, High accuracy metering is an essential feature of an electronic power meter application. Metering accuracy is a most important attribute because inaccurate metering can result in substantial amounts of lost revenue. Moreover, inaccurate metering can also undesirably result in overcharging to customers.  The common sources of metering inaccuracies, or error sources in a meter, include the sensor devices, the sensor conditioning circuitry, the Analog FrontEnd (AFE), and the metering algorithm executed either in a digital processing engine or a microcontroller In this post you will find the description of the implementation of a Two Phase Power Meter firmware featuring Kinetis KM34 device using a metering algorithm known as Filter Based Algorithm. The showed firmware was implemented on the hardware design described in the Reference Manual DRM149 (the software implementation shown in the DRM149 is using a more complex metering algorithm called Fast Fourier Transform). Firmware Design The firmware implements the basic functions for an e-meter application such as: Power meter calibration: Performs power meter calibration and stores calibration parameters. Data processing: Read digital values form the AFE and performs scaling. Calculation of quantities: Calculates billing and non-billing quantities HMI control: Updates LCD with the new values and transitions to new LCD screen. Powe Meter Calibration The calibration task runs whenever a non-calibrated power meter is connected to the mains. First it checks if the calibration flag is already stored in the microcontroller flash, if not, then it runs the calibration. More detail about the calibration process can be found in the DRM143 document. The function: int16 CONFIG_CalcCalibData ( tCONFIG_FLASH_DATA * ptr ) ‍‍ ‍ is in charge of calculating the calibration data and store the calibration flag in the flash. You can refer to the next code section for the complete usage and definition.   /* if calibration data were collected then calibration parameters are       */   /* calculated and saved to flash                                            */   if ( CONFIG_CalcCalibData ( ( tCONFIG_FLASH_DATA * ) & ramcfg ) == TRUE )     CONFIG_SaveFlash ( ( tCONFIG_FLASH_DATA * ) & ramcfg , ramcfg . flag ) ; ‍ ‍ ‍ ‍ The calibration task terminates by storing calibration gains, offsets and phase shift into the flash and by resetting the microcontroller device. Data Processing Reading the phase voltage and phase current samples from the analog front-end (AFE) occurs periodically every 166.6 μs. This task runs on the highest priority level (Level 0) and is triggered asynchronously when the AFE result registers receive new samples. The task reads the phase voltage and phase current samples from the AFE result registers, scales the samples to the full fractional range, and writes the values to the temporary variables for use by the calculation task. While kWh values is being calculated every 6000 Hz the remaining quantities: kVARh, QAVG, PAVG, URMS and IRMS are being calculates every 1500 Hz (666.6 μs). This is according to the decimation factor and to reduce the CPU usage since those values are not needed every AFE sample. The meter definition used for this application can be found in the meterlib2ph_cfg.h files, this file was generated using the Filter-Based Metering Algorithms Configuration Tool, for more information on how to use the tool you can refer to the AN4265 document. This is the Meter configuration: Here you can see the expected error behavior against Frequency: The configuration of the AFE module and channels is the following:   /* Current Phase 1                                                          */   AFE_ChInit ( CH0 ,               AFE_CH_SWTRG_CCM_PGAOFF_CONFIG ( DEC_OSR1024 ) ,                     0 ,               PRI_LVL1 ,               ( AFE_CH_CALLBACK ) NULL ) ;     /* Current Phase 2                                                          */   AFE_ChInit ( CH1 ,               AFE_CH_SWTRG_CCM_PGAOFF_CONFIG ( DEC_OSR1024 ) ,               0 ,               PRI_LVL1 ,               ( AFE_CH_CALLBACK ) NULL ) ;     /* Voltage Phase 1                                                          */   AFE_ChInit ( CH2 ,               AFE_CH_SWTRG_CCM_PGAOFF_CONFIG ( DEC_OSR1024 ) ,                     0 ,               PRI_LVL1 ,               ( AFE_CH_CALLBACK ) NULL ) ;     /* Voltage Phase 2                                                          */      AFE_ChInit ( CH3 ,               AFE_CH_SWTRG_CCM_PGAOFF_CONFIG ( DEC_OSR1024 ) ,               0 ,               PRI_LVL1 ,               ( AFE_CH_CALLBACK ) afech3_callback ) ;     /* AFE Initialization @ 6 KHz                                               */   AFE_Init    ( AFE_MODULE_RJFORMAT_CONFIG ( AFE_PLL_CLK , AFE_DIV2 , 12.288e6 ) ) ;   ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ As you can see only the CH3, which is measuring the Voltage phase 2, is configured with interrupt. During the CH3 callback the remaining channels are sampled to get the 4 values at the same time and performs scaling: /* measurements callback @ 6000 Hz                                            */ static void afech3_callback ( AFE_CH_CALLBACK_TYPE type , int32 result ) {   static int cnt_1 = 0 ;     if ( type == COC_CALLBACK )   {       /* Current and Voltage reading                                            */     u24_sample [ 0 ] = AFE_ChRead ( CH2 ) << U_SCALE ;             /* Voltage 1 reading ... */     i24_sample [ 0 ] = AFE_ChRead ( CH0 ) << I_SCALE ;             /* Current 1 reading ... */     u24_sample [ 1 ] = AFE_ChRead ( CH3 ) << U_SCALE ;             /* Voltage 2 reading ... */     i24_sample [ 1 ] = AFE_ChRead ( CH1 ) << I_SCALE ;             /* Current 2 reading ... */     . . . . } ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ Calculation of Quantities Within the CH3 interrupt the metering algorithm functions are called to process the data of the active energy, the calculation task scales the samples using calibration offsets and calibration gains obtained during the calibration phase: METERLIB2PH_ProcSamples removes DC bias from phase voltage and phase current samples together with performing an optional sensor phase shift correction. METERLIB2PH_CalcWattHours recalculates active energy using new voltage and current samples. CONFIG_UpdateOffsets updates offset of the phase voltage and current measurements conditionally. The CH3 calls the next software interrupt, auxcalc_callback where non-billing quantities are calculated: METERLIB2PH_CalcVarHours recalculates reactive energy. METERLIB2PH_CalcAuxiliary recalculates URMS, IRMS, PAVG, QAVG and S auxiliary quantities. You can find more information about the Filter-Based Algorithm function in the AN4265 document.   HMI Control The display_callback task is called every 3 Hz by the auxcalc_callback and is executed on the lowest priority. For this application it update the clock data structure, refresh the watchdog timer and call some metering algorithm functions to read the values of the billing and non-billing quantities: METERLIB2PH_ReadResultsPh1 reads URMS, IRMS, PAVG, QAVG and S auxiliary quantities from phase 1. METERLIB2PH_ReadResultsPh2 reads URMS, IRMS, PAVG, QAVG and S auxiliary quantities from phase 2. A timer interrupt is used to update the the LCD content every 1500 ms. static void lptmr_callback ( void ) {   lcd_all_off ( ) ;   /* update menu index                                                    */   menu_fcn [ menu_idx ] ( ) ;   if ( ( ++ menu_idx ) >= DIM ( menu_fcn ) )   {     menu_idx = 0 ;   } } ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ Results The two-phase hardware has been calibrated using the test equipment ELMA8303. During accuracy calibration and testing, the power meter measured electrical quantities generated by the test bench, calculated active and reactive energies, and generated pulses on the output LEDs; each generated pulse was equal to the active and reactive energy amount kWh (kVARh)/imp3. The deviations between pulses generated by the power meter and reference pulses generated by test equipment defined the measurement accuracy.   The next figure shows the calibration protocol of the power meter. The protocol indicates the results of the power meter calibration performed at 25 °C. The accuracy and repeatability of the measurement for various phase currents and angles between phase current and phase voltage are shown in these graphs. The first graph indicates the accuracy of the active and reactive energy measurement after calibration. The x-axis shows variation of the phase current, and the y-axis denotes the average accuracy of the power meter computed from five successive measurements The second graph (on the bottom) shows the measurement repeatability; i.e. standard deviation of error of the measurements at a specific load point.  You will find attached a ZIP file containing the IAR source code of the application and a PDF file showing the complete results of the protocol. I hope the information helps. Regards, Adrian Cano
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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&amp;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&amp;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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Download Kinetis M bare-metal drivers and software examples installation file. Changes in 4.1.6 : Modified FreeRTOS kernel to disable all interrupts prior entry to critical section and enable all interrupts upon exiting from critical section. This kernel behavior is compatible with standard FreeRTOS port to the ARM Cortex-M0 core. All freertos_cfg header files updated to reflect kernel change. Updated PLL_Disable macro and Quad Timer driver. Added UART_SetBaudRate macro. Removed RCM_ClrResetFlags macro. Fixed issue of generating callback events after conversion for these ADC channels with interrupt disabled.
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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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Latest version of the AN2295 universal bootloader includes support for IAR 7.6 IDE. - added support for Kinetis E MCUs - Kinetis K,L,M,E,W,V support
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1.jicheng0622-AET-电子技术应用 2.wuyage-AET-电子技术应用 3.fanxi123-AET-电子技术应用
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Revise History: Version 23: NXP kinetis bootloader GUI upgrade from v1.0 to v1.1: added 04 extended linear address record  and 02 sector address record processing for hex format. This article describes how to do in-system reprogramming of Kinetis devices using standard communication media such as SCI. Most of the codes are written in C so that make it easy to migrate to other MCUs. The solution has been already adopted by customers. The pdf document is based on FRDM-KL26 demo board and Codewarrior 10.6.  The bootloader and user application source codes are provided. GUI and video show are also provided. Now the bootloader source code is ported to KDS3.0, Keil5.15 and IAR7.40 which are also enclosed in the SW package. Customer can make their own bootloader applications based on them. The application can be used to upgrade single target board and multi boards connected through networks such as RS485. The bootloader application checks the availability of the nodes between the input address range, and upgrades firmware nodes one by one automatically. ​ Key features of the bootloader: Able to update (or just verify) either single or multiple devices in a network. Application code and bootloader code are in separated projects, convenient for mass production and firmware upgrading. Bootloader code size is small, only around 2K, which reduces the requirement of on chip memory resources. Source code available, easy for reading and migrating. GUI supports S19,HEX and BIN format burning images. For more information, please see attached document and code. The attached demo code is for KL26 which is Cortex - M0+ core. For Cortex-M4 core demo, refer this url: https://community.freescale.com/docs/DOC-328365 User can also download the document and source code from Github: https://github.com/jenniezhjun/Kinetis-Bootloader.git Thanks for the great support from Chaohui Guo and his team. NOTE: The bootloader and GUI code are all open source, users can revise them based on your own requirement. Enjoy Bootloader programming 🙂
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This document explains a potential issue where interrupts appear to be disabled after enterring debug mode. This is as a result of the NMI being active when debug is enabled.
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