UART initialisation

[fabricepeden]

Posted on February 22, 2013 at 09:24

Hi everybody,

I'm using a STM32F205VE and something that I don't understand.I do this :  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_Mode = USART_Mode_Rx | USART_Mode_Tx;  USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;  USART_Init(USART6,&USART_InitStructure);and I can see the configuration into the USART6 register.I do the same thing for USART3 and nothing happen, no registers are configurated.Have you some ideas about this problem ? Must I do something special for this USART ?Thank you in advance,

[waclawek.jan]

Posted on February 22, 2013 at 09:33  *          ===================================================================   *                                 How to use this driver   *          ===================================================================   *          1. Enable peripheral clock using the follwoing functions   *             RCC_APB2PeriphClockCmd(RCC_APB2Periph_USARTx, ENABLE) for USART1 and USART6   *             RCC_APB1PeriphClockCmd(RCC_APB1Periph_USARTx, ENABLE) for USART2, USART3, UART4 or UART5.

[Tesla DeLorean]

Posted on February 22, 2013 at 09:43

For synchronous designs, Rule#1 : Enable the clock.

[fabricepeden]

Posted on February 22, 2013 at 09:50

Sorry, I think I will post all my code, it would be easier for everybody.

 /* COM1 - NETWORK OUT */  RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART6, ENABLE);  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC,ENABLE);    GPIO_PinAFConfig(EVAL_COM1_TX_GPIO_PORT,EVAL_COM1_TX_SOURCE,EVAL_COM1_TX_AF);  GPIO_PinAFConfig(EVAL_COM1_RX_GPIO_PORT,EVAL_COM1_RX_SOURCE,EVAL_COM1_RX_AF);    /* Configure USART Tx and Rx as alternate function push-pull */  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_UP;  GPIO_InitStructure.GPIO_Pin = EVAL_COM1_TX_PIN;  GPIO_Init(EVAL_COM1_TX_GPIO_PORT, &GPIO_InitStructure);    GPIO_InitStructure.GPIO_Pin = EVAL_COM1_RX_PIN;  GPIO_Init(EVAL_COM1_RX_GPIO_PORT, &GPIO_InitStructure);    /* Configuration : 115200 bauds, 8 N 1 */  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_Mode = USART_Mode_Rx | USART_Mode_Tx;  USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;    /*USART_OverSampling8Cmd(EVAL_COM1,ENABLE);*/    USART_Init(EVAL_COM1,&USART_InitStructure);   /* Enable the USARTx Interrupt */  NVIC_InitStructure.NVIC_IRQChannel = EVAL_COM1_IRQn;  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;  NVIC_Init(&NVIC_InitStructure);    USART_ITConfig(EVAL_COM1, USART_IT_TXE, DISABLE);  USART_ITConfig(EVAL_COM1, USART_IT_RXNE, ENABLE);    /* Enable USART */  USART_Cmd(EVAL_COM1, ENABLE);    /* Configuration de la PIN REDE */  COMRDInit(COM1);    /* COM2 - NETWORK IN */  /* COM1 - NETWORK OUT */  RCC_APB2PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD,ENABLE);    GPIO_PinAFConfig(EVAL_COM2_TX_GPIO_PORT,EVAL_COM2_TX_SOURCE,EVAL_COM2_TX_AF);  GPIO_PinAFConfig(EVAL_COM2_RX_GPIO_PORT,EVAL_COM2_RX_SOURCE,EVAL_COM2_RX_AF);    /* Configure USART Tx and Rx as alternate function push-pull */  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_UP;  GPIO_InitStructure.GPIO_Pin = EVAL_COM2_TX_PIN;  GPIO_Init(EVAL_COM2_TX_GPIO_PORT, &GPIO_InitStructure);    GPIO_InitStructure.GPIO_Pin = EVAL_COM2_RX_PIN;  GPIO_Init(EVAL_COM2_RX_GPIO_PORT, &GPIO_InitStructure);    /* Configuration : 115200 bauds, 8 N 1 */  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_Mode = USART_Mode_Rx | USART_Mode_Tx;  USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;  USART_Init(EVAL_COM2,&USART_InitStructure);   /* Enable the USARTx Interrupt */  NVIC_InitStructure.NVIC_IRQChannel = EVAL_COM2_IRQn;  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0F;  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0F;  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;  NVIC_Init(&NVIC_InitStructure);    USART_ITConfig(EVAL_COM2, USART_IT_TC, ENABLE);  USART_ITConfig(EVAL_COM2, USART_IT_RXNE, ENABLE);     /* Enable USART */  USART_Cmd(EVAL_COM2, ENABLE);    /* Configuration de la PIN REDE */  COMRDInit(COM2);

[waclawek.jan]

Posted on February 22, 2013 at 11:04

>   RCC_APB2PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);

 *          ===================================================================   *                                 How to use this driver   *          ===================================================================   *          1. Enable peripheral clock using the follwoing functions   *             RCC_APB2PeriphClockCmd(RCC_APB2Periph_USARTx, ENABLE) for USART1 and USART6   *             RCC_APB1PeriphClockCmd(RCC_APB1Periph_USARTx, ENABLE) for USART2, USART3, UART4 or UART5. JW

[fabricepeden]

Posted on February 22, 2013 at 15:24

Thank you for your answer.

Now my registers are well configured.I'll see if my UART is working !