Documentation / spi / spidev_test.c

最新推荐文章于 2025-07-01 13:35:00 发布

原创

最新推荐文章于 2025-07-01 13:35:00 发布 · 2.1k 阅读

1 ·

CC 4.0 BY-SA版权

本文档是Linux系统下用于SPI设备测试的spidev_test.c源码解析，它包含了一个简单的SPI传输流程，并展示了如何配置SPI模式、速度、延迟等参数。代码中还包含了数据发送、接收及调试输出的功能。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

/*
* SPI testing utility (using spidev driver)
*
* Copyright (c) 2007 MontaVista Software, Inc.
* Copyright (c) 2007 Anton Vorontsov <avorontsov@ru.mvista.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License.
*
* Cross-compile with cross-gcc -I/path/to/cross-kernel/include
*/

#include <stdint.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/types.h>
#include <linux/spi/spidev.h>

#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))

static void pabort(const char *s)
{
perror(s);
abort();
}

static const char *device = "/dev/spidev1.1";
static uint32_t mode;
static uint8_t bits = 8;
static uint32_t speed = 500000;
static uint16_t delay;
static int verbose;

uint8_t default_tx[] = {
   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
   0x40, 0x00, 0x00, 0x00, 0x00, 0x95,
   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
   0xF0, 0x0D,
};

uint8_t default_rx[ARRAY_SIZE(default_tx)] = {0, };
char *input_tx;

static void hex_dump(const void *src, size_t length, size_t line_size, char *prefix)
{
   int i = 0;
   const unsigned char *address = src;
   const unsigned char *line = address;
   unsigned char c;

   printf("%s | ", prefix);
   while (length-- > 0) {
       printf("%02X ", *address++);
       if (!(++i % line_size) || (length == 0 && i % line_size)) {
           if (length == 0) {
               while (i++ % line_size)
                   printf("__ ");
           }
           printf(" | "); /* right close */
           while (line < address) {
               c = *line++;
               printf("%c", (c < 33 || c == 255) ? 0x2E : c);
           }
           printf("\n");
           if (length > 0)
       &