usb_hid编程

通过上位机软件给英飞凌芯片发送信号，模拟喷油，节气门开度等信息，但是在重复发送命令和reset过程中，会出现读取不到数据的情况，调查了好久也没有找到原因，与下位机通信的接口都是调用的微软封装的SetupDi系列函数，但是总是读不上来数据，问题原因有待调查，今天找到了HID API的纯C封装版本，而且跨平台，看了下介绍，很强大，记录下来。先贴例子程序

/*******************************************************
 Windows HID simplification

 Alan Ott
 Signal 11 Software

 8/22/2009

 Copyright 2009, All Rights Reserved.
 
 This contents of this file may be used by anyone
 for any reason without any conditions and may be
 used as a starting point for your own applications
 which use HIDAPI.
********************************************************/

#include <stdio.h>
#include <wchar.h>
#include <string.h>
#include <stdlib.h>
#include "hidapi.h"

// Headers needed for sleeping.
#ifdef _WIN32
    #include <windows.h>
#else
    #include <unistd.h>
#endif

int main(int argc, char* argv[])
{
    int res;
    unsigned char buf[256];
    #define MAX_STR 255
    wchar_t wstr[MAX_STR];
    hid_device *handle;
    int i;

#ifdef WIN32
    UNREFERENCED_PARAMETER(argc);
    UNREFERENCED_PARAMETER(argv);
#endif

    struct hid_device_info *devs, *cur_dev;
    
    if (hid_init())
        return -1;

    devs = hid_enumerate(0x0, 0x0);
    cur_dev = devs;    
    while (cur_dev) {
        printf("Device Found
  type: %04hx %04hx
  path: %s
  serial_number: %ls", cur_dev->vendor_id, cur_dev->product_id, cur_dev->path, cur_dev->serial_number);
        printf("
");
        printf("  Manufacturer: %ls
", cur_dev->manufacturer_string);
        printf("  Product:      %ls
", cur_dev->product_string);
        printf("  Release:      %hx
", cur_dev->release_number);
        printf("  Interface:    %d
",  cur_dev->interface_number);
        printf("
");
        cur_dev = cur_dev->next;
    }
    hid_free_enumeration(devs);

    // Set up the command buffer.
    memset(buf,0x00,sizeof(buf));
    buf[0] = 0x01;
    buf[1] = 0x81;
    

    // Open the device using the VID, PID,
    // and optionally the Serial number.
    ////handle = hid_open(0x4d8, 0x3f, L"12345");
    handle = hid_open(0x4d8, 0x3f, NULL);
    if (!handle) {
        printf("unable to open device
");
         return 1;
    }

    // Read the Manufacturer String
    wstr[0] = 0x0000;
    res = hid_get_manufacturer_string(handle, wstr, MAX_STR);
    if (res < 0)
        printf("Unable to read manufacturer string
");
    printf("Manufacturer String: %ls
", wstr);

    // Read the Product String
    wstr[0] = 0x0000;
    res = hid_get_product_string(handle, wstr, MAX_STR);
    if (res < 0)
        printf("Unable to read product string
");
    printf("Product String: %ls
", wstr);

    // Read the Serial Number String
    wstr[0] = 0x0000;
    res = hid_get_serial_number_string(handle, wstr, MAX_STR);
    if (res < 0)
        printf("Unable to read serial number string
");
    printf("Serial Number String: (%d) %ls", wstr[0], wstr);
    printf("
");

    // Read Indexed String 1
    wstr[0] = 0x0000;
    res = hid_get_indexed_string(handle, 1, wstr, MAX_STR);
    if (res < 0)
        printf("Unable to read indexed string 1
");
    printf("Indexed String 1: %ls
", wstr);

    // Set the hid_read() function to be non-blocking.
    hid_set_nonblocking(handle, 1);
    
    // Try to read from the device. There shoud be no
    // data here, but execution should not block.
    res = hid_read(handle, buf, 17);

    // Send a Feature Report to the device
    buf[0] = 0x2;
    buf[1] = 0xa0;
    buf[2] = 0x0a;
    buf[3] = 0x00;
    buf[4] = 0x00;
    res = hid_send_feature_report(handle, buf, 17);
    if (res < 0) {
        printf("Unable to send a feature report.
");
    }

    memset(buf,0,sizeof(buf));

    // Read a Feature Report from the device
    buf[0] = 0x2;
    res = hid_get_feature_report(handle, buf, sizeof(buf));
    if (res < 0) {
        printf("Unable to get a feature report.
");
        printf("%ls", hid_error(handle));
    }
    else {
        // Print out the returned buffer.
        printf("Feature Report
   ");
        for (i = 0; i < res; i++)
            printf("%02hhx ", buf[i]);
        printf("
");
    }

    memset(buf,0,sizeof(buf));

    // Toggle LED (cmd 0x80). The first byte is the report number (0x1).
    buf[0] = 0x1;
    buf[1] = 0x80;
    res = hid_write(handle, buf, 17);
    if (res < 0) {
        printf("Unable to write()
");
        printf("Error: %ls
", hid_error(handle));
    }
    

    // Request state (cmd 0x81). The first byte is the report number (0x1).
    buf[0] = 0x1;
    buf[1] = 0x81;
    hid_write(handle, buf, 17);
    if (res < 0)
        printf("Unable to write() (2)
");

    // Read requested state. hid_read() has been set to be
    // non-blocking by the call to hid_set_nonblocking() above.
    // This loop demonstrates the non-blocking nature of hid_read().
    res = 0;
    while (res == 0) {
        res = hid_read(handle, buf, sizeof(buf));
        if (res == 0)
            printf("waiting...
");
        if (res < 0)
            printf("Unable to read()
");
        #ifdef WIN32
        Sleep(500);
        #else
        usleep(500*1000);
        #endif
    }

    printf("Data read:
   ");
    // Print out the returned buffer.
    for (i = 0; i < res; i++)
        printf("%02hhx ", buf[i]);
    printf("
");

    hid_close(handle);

    /* Free static HIDAPI objects. */
    hid_exit();

#ifdef WIN32
    system("pause");
#endif

    return 0;
}

网站地址： http://www.signal11.us/oss/hidapi/

为了方便读者的使用，我已经编译出了一个版本，可以直接下载，压缩包里有dll和lib两个版本。

http://pan.baidu.com/s/1DuNEP