Car/Core/Inc/syscalls.h

#ifndef __SYSCALLS_H
#define __SYSCALLS_H

#include <errno.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <stm32f1xx_hal_uart.h>
#include <time.h>

#define HUART1 (&huart1)
#define HUART2 (&huart2)

extern UART_HandleTypeDef huart2;

extern int __io_putchar(int ch) __attribute__((weak));
extern int __io_getchar(void) __attribute__((weak));

__attribute__((weak)) int _read(int file, char *ptr, int len) {
    (void)file;
    int DataIdx;

    for (DataIdx = 0; DataIdx < len; DataIdx++) {
        *ptr++ = __io_getchar();
    }

    return len;
}

__attribute__((weak)) int _write(int file, char *ptr, int len) {
    (void)file;
    int DataIdx;

    for (DataIdx = 0; DataIdx < len; DataIdx++) {
        __io_putchar(*ptr++);
    }
    return len;
}

// 条件编译
#ifdef __GNUC__
#define PUTCHAR_PROTOTYPE int __io_putchar(int ch)
#define GETCHAR_PROTOTYPE int __io_getchar(void)
#else
#define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)
#define GETCHAR_PROTOTYPE int fgetc(FILE *f)
#endif /* __GNUC__ */

/**
 * @brief 重定向 C 标准库 printf 函数到串口 huart2
 * @author Suroy
 * @param ch
 * @param f
 * @return int
 *
 * @usage printf("USART1_Target:\r\n");
 */
PUTCHAR_PROTOTYPE {
    HAL_UART_Transmit(&huart2, (uint8_t *)&ch, 1, HAL_MAX_DELAY); // 阻塞式无限等待
    return ch;
}

/**
 * @brief 重定向 c库函数 getchar,scanf到 DEBUG_USARTx
 * 重定向 C 标准库 scanf 函数到串口 huart2
 * 注意以 空格 为结束
 * @param f
 * @return int
 *
 * @usage scanf("%c", &RecData);
 */
GETCHAR_PROTOTYPE {
    uint8_t ch = 0;
    HAL_UART_Receive(&huart2, (uint8_t *)&ch, 1, HAL_MAX_DELAY);
    return ch;
}

void delay_us(uint16_t us) {
    uint32_t delay = (HAL_RCC_GetHCLKFreq() / 4000000 * us);
    while (delay--);
}

/**
 * @brief 自定义printf
 * @param huart, buf
 * @return void
 *
 * @usage my_printf(HUART1, "USART1_Target:\r\n");
 */
void my_printf(UART_HandleTypeDef *huart, const char *buf, ...) {
    const char *p = buf;
    char str[255] = {0};
    va_list v;
    va_start(v, buf);
    vsprintf(str, buf, v);
    HAL_UART_Transmit(huart, str, strlen(str), 0xff);
    va_end(v);
}


#endif