linux spi 时钟频率

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

int main() {
    int fd;
    struct spi_ioc_transfer tr;
    uint8_t tx[] = {0x01, 0x80, 0x00};
    uint8_t rx[3] = {0};

    fd = open("/dev/spidev0.0", 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 = sizeof(tx);
    tr.speed_hz = 1000000; // 设置时钟频率为1MHz
    tr.delay_usecs = 0;
    tr.bits_per_word = 8;

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

    printf("Received: %02X %02X %02X\n", rx[0], rx[1], rx[2]);

    close(fd);
    return 0;
}