Help me USART STM32F4

[pattaradanai]

Posted on August 09, 2013 at 18:34

What is wrong. it isn't show data in terminal,

********************************************************************** &sharpinclude <stm32f4xx.h> &sharpinclude <stm32f4xx_rcc.h> &sharpinclude <stm32f4xx_gpio.h> &sharpinclude <main.h> &sharpinclude <stm32f4xx_usart.h> &sharpinclude <stdio.h> //****************************************************************************** char str[14]; char msg1; int msg; //********************** Function *********************************************** void USART_SETUP (void); void delay(void); void USART1_PUTC(unsigned char c); void USART1_PUTS(unsigned char *s); int USART1_GETC(void); //************************ Main Function *************************************** int main() {     USART_SETUP();   STM_EVAL_LEDInit(LED3);   STM_EVAL_LEDInit(LED4);   STM_EVAL_LEDInit(LED5);   STM_EVAL_LEDInit(LED6);     STM_EVAL_LEDOn(LED6);   while(1)   {         while(USART_GetFlagStatus(USART1,USART_FLAG_RXNE)==RESET);         msg1 = USART_ReceiveData(USART1);         while(USART_GetFlagStatus(USART1,USART_FLAG_TXE)==RESET);         USART_SendData(USART1,msg1);   }     } //*************************************************************************** void delay (void) {   unsigned int i,j;   for(i=0;i<5000;i++)     {         for(j=0;j<700;j++);     } } //***************************** USART_SETUP ******************************* void USART_SETUP(void) {     GPIO_InitTypeDef GPIO_InitStruct;     USART_InitTypeDef USART_InitStruct;          RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);     /*         USART2 use port A and pin 8-12             PA8  is USART1_CK             PA9  is USART1_TX             PA10 is USART1_RX             PA11 is USART1_CTS             PA12 is USART1_RTS     */     RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);          GPIO_PinAFConfig(GPIOA,GPIO_PinSource9,GPIO_AF_USART1);     GPIO_PinAFConfig(GPIOA,GPIO_PinSource10,GPIO_AF_USART1);          /* Configure PA2  in AF pushpull mode */   GPIO_InitStruct.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10 ;   GPIO_InitStruct.GPIO_Speed = GPIO_Speed_100MHz;     GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;   GPIO_InitStruct.GPIO_PuPd  = GPIO_PuPd_NOPULL;   GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;   GPIO_Init(GPIOA, &GPIO_InitStruct);          /* USARTx configured as follow:         - BaudRate = 9600 baud           - Word Length = 8 Bits         - One Stop Bit         - No parity         - Hardware flow control disabled (RTS and CTS signals)         - Receive and transmit enabled   */   USART_InitStruct.USART_BaudRate = 115200;   USART_InitStruct.USART_WordLength = USART_WordLength_8b;   USART_InitStruct.USART_StopBits = USART_StopBits_1;   USART_InitStruct.USART_Parity = USART_Parity_No;   USART_InitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;   USART_InitStruct.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;     USART_Init(USART1, &USART_InitStruct);                    USART_Cmd(USART1, ENABLE); } void USART1_PUTC(unsigned char c) {     while(USART_GetFlagStatus(USART1,USART_FLAG_TXE)==RESET);     USART_SendData(USART1,(int) c); } void USART1_PUTS(unsigned char *s) {     while(*s)     {         USART1_PUTC(*s++);     } } int USART1_GETC(void) {     while(USART_GetFlagStatus(USART1,USART_FLAG_RXNE)==RESET);     return(USART_ReceiveData(USART1));         } #stm32f4 #usart #rs232

[Tesla DeLorean]

Posted on August 12, 2013 at 00:45

You haven't explicitly stated that you're using an STM32F4-Discovery board, but if you are PA9 is not usable for a USART pin due to a huge bulk capacitor being attached to it.

Might help if your comments were somewhat coherent with the code. A secondary issue with USART functionality is with timing, from both the perspective of the external crystal used, and the value defined for HSE_VALUE. Thirdly, the output/input for the STM32 is CMOS levels, this is NOT compatible with RS232 levels, and requires some interface circuitry.

[ran2]

Posted on August 12, 2013 at 10:34

Is this going to display some characters on your PC?

[Tesla DeLorean]

Posted on August 13, 2013 at 18:20

Is this going to display some characters on your PC?

The example as presented attempts to echo back received characters to the sender, presumably a terminal app on a PC.

[pattaradanai]

Posted on August 14, 2013 at 06:24

First, I define HSE_Value = 8000000 in option and headfile stm32f4xx.h

Secondly, I connect port USART with interface circuit with MAX3232 Third, I connect port PA9 follow Datasheet STM32F407 and it same problem Thank you

[pattaradanai]

Posted on August 14, 2013 at 06:28

Yes, It show some character but it not english character.

 

[Tesla DeLorean]

Posted on August 14, 2013 at 14:03

Reinterating, PA9 is NOT usable on the STM32F4-Discovery board

Send a stream of characters, review signal on scope.