linux I2C总线编程

sudo apt-get update
sudo apt-get install i2c-tools libi2c-dev

#include <stdio.h>
#include <stdlib.h>
#include <linux/i2c-dev.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <unistd.h>

#define I2C_BUS "/dev/i2c-1"  // 根据实际情况修改
#define DEVICE_ADDR 0x5A       // I2C设备地址

int main() {
    int file;
    char *bus = I2C_BUS;
    if ((file = open(bus, O_RDWR)) < 0) {
        perror("Failed to open the i2c bus");
        return 1;
    }

    int addr = DEVICE_ADDR;
    if (ioctl(file, I2C_SLAVE, addr) < 0) {
        perror("Failed to acquire bus access and/or talk to slave.");
        return 1;
    }

    char buf[2];
    buf[0] = 0x01;  // 假设我们要读取寄存器0x01的值
    if (write(file, buf, 1) != 1) {
        perror("Error writing to i2c slave");
        return 1;
    }

    if (read(file, buf, 1) != 1) {
        perror("Error reading from i2c slave");
        return 1;
    }

    printf("Register 0x01 value: 0x%02X\n", buf[0]);

    close(file);
    return 0;
}