c语言实现usb接口协议源码

实现 USB 接口协议需要用到 USB 主机控制器和 USB 设备控制器的驱动程序，这些驱动程序需要直接与硬件进行交互。因此，编写 USB 接口协议的源码需要深入了解 USB 协议和硬件驱动程序的开发。

以下是一个简单的 C 语言实现 USB 接口协议源码示例，仅供参考：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <stdbool.h>
#include <usb.h>

#define VENDOR_ID 0x1234
#define PRODUCT_ID 0x5678
#define ENDPOINT_IN 0x81
#define ENDPOINT_OUT 0x01
#define MAX_PACKET_SIZE 64

struct usb_dev_handle *open_device(void){
    struct usb_bus *bus;
    struct usb_device *dev;
    struct usb_dev_handle *handle = NULL;

    usb_init();
    usb_find_busses();
    usb_find_devices();

    for(bus = usb_get_busses(); bus; bus = bus->next){
        for(dev = bus->devices; dev; dev = dev->next){
            if(dev->descriptor.idVendor == VENDOR_ID && dev->descriptor.idProduct == PRODUCT_ID){
                handle = usb_open(dev);
                break;
            }
        }
        if(handle) break;
    }

    if(!handle){
        fprintf(stderr, "Device not found\n");
        exit(1);
    }

    if(usb_set_configuration(handle, 1) < 0){
        fprintf(stderr, "Could not set configuration\n");
        usb_close(handle);
        exit(1);
    }

    if(usb_claim_interface(handle, 0) < 0){
        fprintf(stderr, "Could not claim interface\n");
        usb_close(handle);
        exit(1);
    }

    return handle;
}

void close_device(struct usb_dev_handle *handle){
    usb_release_interface(handle, 0);
    usb_close(handle);
}

void send_data(struct usb_dev_handle *handle, uint8_t *data, uint32_t size){
    int transferred = usb_bulk_write(handle, ENDPOINT_OUT, data, size, 1000);
    if(transferred < 0){
        fprintf(stderr, "Error sending data: %s\n", usb_strerror());
        exit(1);
    }
}

void receive_data(struct usb_dev_handle *handle, uint8_t *data, uint32_t size){
    int transferred = usb_bulk_read(handle, ENDPOINT_IN, data, size, 1000);
    if(transferred < 0){
        fprintf(stderr, "Error receiving data: %s\n", usb_strerror());
        exit(1);
    }
}

int main(int argc, char **argv){
    struct usb_dev_handle *handle;
    uint8_t buf[MAX_PACKET_SIZE];
    uint32_t size;

    handle = open_device();

    // Send some data
    memset(buf, 0x55, MAX_PACKET_SIZE);
    send_data(handle, buf, MAX_PACKET_SIZE);

    // Receive some data
    receive_data(handle, buf, MAX_PACKET_SIZE);
    size = usb_get_max_packet_size(handle, ENDPOINT_IN);
    printf("Received %d bytes of data\n", size);

    close_device(handle);

    return 0;
}

该示例使用 libusb 库进行 USB 设备操作，实现了 USB 数据的发送和接收。其中，`open_device` 函数用于打开 USB 设备，`close_device` 函数用于关闭设备，`send_data` 函数用于发送数据，`receive_data` 函数用于接收数据。具体实现过程中，需要根据硬件和协议的要求进行相应的配置和处理。