xuart.c

#include <stm32f10x.h>
#include <stm32f10x_rcc.h>
#include <stm32f10x_gpio.h>
#include <stm32f10x_usart.h>
#include "xuart.h"


// define buffers here.

int uart_open (USART_TypeDef* USARTx, uint32_t baud, uint32_t flags)
{
  USART_InitTypeDef USART_InitStructure; 
  GPIO_InitTypeDef GPIO_InitStructureTx; 
  GPIO_InitTypeDef GPIO_InitStructureRx;

  assert_param(IS_USART_123_PERIPH(USARTx));

  if (USARTx == USART1) {

    // Turn on clocks

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA  |
			   RCC_APB2Periph_AFIO,
			   ENABLE);

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);

    // Configure TX pin

    GPIO_InitStructureTx.GPIO_Pin = GPIO_Pin_9;
    GPIO_InitStructureTx.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructureTx.GPIO_Speed = GPIO_Speed_50MHz; 
    GPIO_Init(GPIOA, &GPIO_InitStructureTx);

    // Configure RX pin

    GPIO_InitStructureRx.GPIO_Pin = GPIO_Pin_10;
    GPIO_InitStructureRx.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructureRx);

    // Configure the UART

    USART_StructInit(&USART_InitStructure); 
    USART_InitStructure.USART_BaudRate = baud;
    USART_InitStructure.USART_Mode  = USART_Mode_Rx | USART_Mode_Tx;
    USART_Init(USART1,&USART_InitStructure); 
    USART_Cmd(USART1, ENABLE); 

    return 0;
  } 
}


int uart_close(USART_TypeDef* USARTx)
{
    assert_param(IS_USART_123_PERIPH(USARTx));
}

void uart_putc(unsigned char c)
{
  assert_param(IS_USART_123_PERIPH(USART1));

  while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
  USART1->DR =  (c & 0xff);

}

unsigned char uart_getc (void)
{
  assert_param(IS_USART_123_PERIPH(USART1));

  while (USART_GetFlagStatus(USART1, USART_FLAG_RXNE) == RESET);
  return  (unsigned char) USART1->DR & 0xff;
}