linux spi read

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

#define SPI_DEVICE "/dev/spidev0.0"
#define BUFFER_SIZE 10

int main() {
    int fd;
    struct spi_ioc_transfer tr;
    unsigned char tx[BUFFER_SIZE] = {0x01, 0x80, 0x00}; // 发送的数据
    unsigned char rx[BUFFER_SIZE];

    fd = open(SPI_DEVICE, O_RDWR);
    if (fd < 0) {
        perror("Failed to open SPI device");
        return -1;
    }

    memset(&tr, 0, sizeof(tr));
    tr.tx_buf = (unsigned long)tx;
    tr.rx_buf = (unsigned long)rx;
    tr.len = BUFFER_SIZE;
    tr.speed_hz = 500000; // 设置SPI时钟频率
    tr.delay_usecs = 0;

    if (ioctl(fd, SPI_IOC_MESSAGE(1), &tr) < 0) {
        perror("SPI transfer failed");
        close(fd);
        return -1;
    }

    printf("Received data: ");
    for (int i = 0; i < BUFFER_SIZE; i++) {
        printf("%02X ", rx[i]);
    }
    printf("\n");

    close(fd);
    return 0;
}