linux i2c 读写设备

sudo apt-get install i2c-tools
sudo i2cdetect -y 1

sudo usermod -aG i2c $USER
sudo modprobe i2c-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"
#define DEVICE_ADDRESS 0x50

int main() {
    int file;
    char *bus = I2C_BUS;

    if ((file = open(bus, O_RDWR)) < 0) {
        perror("Failed to open the bus.");
        return 1;
    }

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

    // Write data to the device
    char write_data = 0xAA;
    if (write(file, &write_data, 1) != 1) {
        perror("Failed to write to the i2c bus.");
    }

    // Read data from the device
    char read_data;
    if (read(file, &read_data, 1) != 1) {
        perror("Failed to read from the i2c bus.");
    } else {
        printf("Read data: 0x%02X\n", read_data);
    }

    close(file);
    return 0;
}