Files
zjui-ece445/stm32/Src/printf.c

23 lines
540 B
C

#include <errno.h>
#include <sys/unistd.h> // STDOUT_FILENO, STDERR_FILENO
#include <stdint.h>
#include "main.h"
extern UART_HandleTypeDef huart1;
#define PRINT_DEVICE huart1
int _write(int file, char *data, int len)
{
if ((file != STDOUT_FILENO) && (file != STDERR_FILENO))
{
errno = EBADF;
return -1;
}
// arbitrary timeout 1000
HAL_StatusTypeDef status = HAL_UART_Transmit(&huart1, (uint8_t*)data, len, 1000);
// return # of bytes written - as best we can tell
return (status == HAL_OK ? len : 0);
}