STM32F373 USART2 Problem

[fslhusni]

Posted on May 11, 2015 at 13:14

Hello, I have some problem with USART2 (stm32f373). USART1 is working with same code but, Usart2 does not work.  here is the code.

void Uart_Int(void) {   GPIO_InitTypeDef GPIO_InitStructure;   USART_InitTypeDef USART_InitStructure;   USART_ClockInitTypeDef USART_ClockInitStructure;     USART_ClockStructInit(&USART_ClockInitStructure);   USART_ClockInit(USART2, &USART_ClockInitStructure);       RCC_APB2PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);     RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA , ENABLE);     GPIO_PinAFConfig(GPIOA, GPIO_PinSource2, GPIO_AF_7);   GPIO_PinAFConfig(GPIOA, GPIO_PinSource3, GPIO_AF_7);       GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;   GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;//---------   GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;   GPIO_Init(GPIOA, &GPIO_InitStructure);       GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;   GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;//---------   GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;   GPIO_Init(GPIOA, &GPIO_InitStructure);     USART_InitStructure.USART_BaudRate =9600;   USART_InitStructure.USART_WordLength = USART_WordLength_8b;   USART_InitStructure.USART_StopBits = USART_StopBits_1;   USART_InitStructure.USART_Parity = USART_Parity_No;   USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;   USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;   USART_Init(USART2, &USART_InitStructure);   USART_Cmd(USART2, ENABLE); /**/   } int main(void) {    unsigned char data=0;     Uart_Int();        //     while(1)     {                while (USART_GetFlagStatus(USART2, USART_FLAG_TXE) == RESET);   USART_SendData( USART2, 'a');         }  } what kind of problem it has.....?

[Tesla DeLorean]

Posted on May 11, 2015 at 13:27

RCC_APB2PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE); // APB1 APB1 - Fix This

You can also lose the USART_Clock stuff, it doesn't do anything, isn't needed, and it is in the wrong spot.

[fslhusni]

Posted on June 20, 2015 at 13:17

Thank you so much clive1, problem solved.

[fslhusni]

Posted on June 20, 2015 at 13:48

Dear Clive1, Now i am using STM32f0 discovery board,(stm32f051r), i want to transmitte and receive Uart1 data over DMA, if i used Circular mode then any character received through uart1 send continuously, and if  i used normal mode then nothing happen. no data receive or transmite, here is my code.

#include ''main.h'' uint8_t AckBuffer [0x02] = {0x00, 0x00}; static void USART_Config(void); DMA_InitTypeDef DMA_InitStructure; int main(void) {       USART_Config();           //----------------            DMA_DeInit(DMA1_Channel3);       DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&USART1->RDR;//USARTx_TDR_ADDRESS;//       DMA_InitStructure.DMA_BufferSize = (uint16_t)1;       DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)AckBuffer;       DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;       DMA_InitStructure.DMA_Priority = DMA_Priority_High;       DMA_Init(DMA1_Channel3, &DMA_InitStructure);                DMA_DeInit(DMA1_Channel2);       DMA_InitStructure.DMA_PeripheralBaseAddr =(uint32_t)&USART1->TDR; //USARTx_TDR_ADDRESS;//       DMA_InitStructure.DMA_BufferSize = (uint16_t)1;       DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)AckBuffer;       DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;       DMA_InitStructure.DMA_Priority = DMA_Priority_High;       DMA_Init(DMA1_Channel2, &DMA_InitStructure);                            USART_DMACmd(USART1, USART_DMAReq_Rx, ENABLE);       USART_DMACmd(USART1, USART_DMAReq_Tx, ENABLE);              DMA_Cmd(DMA1_Channel2, ENABLE);       DMA_Cmd(DMA1_Channel3, ENABLE);                                   USART_ClearFlag(USART1, USART_FLAG_TC);       DMA_ClearFlag(DMA1_FLAG_GL2);       DMA_ClearFlag(DMA1_FLAG_GL3);              while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);     USART_SendData( USART1, 'F');     //------------------     while (1)   {}   } static void USART_Config(void) {   USART_InitTypeDef USART_InitStructure;   GPIO_InitTypeDef GPIO_InitStructure;       RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA | RCC_AHBPeriph_GPIOA, ENABLE);   USARTx_APBPERIPHCLOCK(RCC_APB2Periph_USART1, ENABLE);   RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);     GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_1);   GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_1);   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_Level_3;   GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;   GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;     GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;   GPIO_Init(GPIOA, &GPIO_InitStructure);     GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;   GPIO_Init(GPIOA, &GPIO_InitStructure);     USART_InitStructure.USART_BaudRate = 115200;   USART_InitStructure.USART_WordLength = USART_WordLength_8b;   USART_InitStructure.USART_StopBits = USART_StopBits_1;   USART_InitStructure.USART_Parity = USART_Parity_No;   USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;   USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;   USART_Init(USARTx, &USART_InitStructure);     DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;   DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;   DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;   DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Disable;//Enable;   DMA_InitStructure.DMA_Mode =DMA_Mode_Circular; //DMA_Mode_Normal;//   DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;        USART_Cmd(USARTx, ENABLE); } #ifdef  USE_FULL_ASSERT void assert_failed(uint8_t* file, uint32_t line) {   /* Infinite loop */   while (1)   {   } } #endif

[fslhusni]

Posted on June 21, 2015 at 15:55

[Tesla DeLorean]

Posted on June 21, 2015 at 16:16

Not sure I see the value of single byte DMA.

In normal mode you'd need to reconfigure the DMA after each byte is sent or received. I don't see any code managing that.

[fslhusni]

Posted on June 21, 2015 at 20:38

[Tesla DeLorean]

Posted on June 22, 2015 at 01:43

Watch that you top post responses, and avoid using phone/tablet devices which don't' work well with this Microsoft ''forum'' software.