符合HID的触摸屏包数据结构

Question

我需要找出符合 HID 标准的触摸屏（单点触摸）输入数据结构（如字节顺序和每个字节应写入的内容）。

我使用了微软官方的 HID 兼容触摸屏描述符 docs

并且在使用设备管理器的主机 PC 中，我能够看到它成功地枚举了 HID 兼容设备。现在我想向主机发送 HID 报告，但问题是我还没有找到类似 HID 触摸屏启动协议的东西（对于鼠标和键盘，它在 USB 组织规范中有明确定义）。这是我用来创建触摸屏 HID 报告的代码示例，它可以正常工作，但不如预期。我通过研究大量 github 代码和阅读文章找到了这种字节组合，但我想找到一些文档来证明顺序是正确的。

    char report[8] = {0};
    uint16_t x_access = 10000;
    uint16_t y_access = 10000;

    report[0] = 0x01; //reportid
    report[1] = 0x3;   //statuss
    report[2] = LOWBYTE(x_access);  //x low byte
    report[3] = HIGHBYTE(x_access); //x high byte
    report[4] = LOWBYTE(y_access);  //y low byte
    report[5] = HIGHBYTE(y_access); //y high byte
    report[6] = 0x65;               //touch parsing time low byte 
    report[7] = 0x00;               //touch parsing time high byte
  //report[8] = 1                   //this doesn't have any impact (touch count)

我用过的有用链接

在此先感谢您的帮助

Answer 1

与RDD! HID Report Descriptor Decoder tool we can easily generate C structs from Microsoft provided touchscreen "Sample Report Descriptor":

//--------------------------------------------------------------------------------
// Digitizer Device Page inputReport 01 (Device --> Host)
//--------------------------------------------------------------------------------

typedef struct
{
  uint8_t  reportId;                                 // Report ID = 0x01 (1)
                                                     // Collection: CA:TouchScreen CL:Finger
  uint8_t  DIG_TouchScreenFingerTipSwitch : 1;       // Usage 0x000D0042: Tip Switch, Value = 0 to 1
  uint8_t  : 7;                                      // Pad
  uint8_t  DIG_TouchScreenFingerContactIdentifier;   // Usage 0x000D0051: Contact Identifier, Value = 0 to 1
  uint16_t GD_TouchScreenFingerX[2];                 // Usage 0x00010030: X, Value = 0 to 4095, Physical = Value x 241 / 819 in 10⁻² inch units
  uint16_t GD_TouchScreenFingerY[2];                 // Usage 0x00010031: Y, Value = 0 to 4095, Physical = Value x 302 / 1365 in 10⁻² inch units
  uint16_t DIG_TouchScreenFingerWidth;               // Usage 0x000D0048: Width, Value = 0 to 4095, Physical = Value x 302 / 1365 in 10⁻² inch units
  uint16_t DIG_TouchScreenFingerHeight;              // Usage 0x000D0049: Height, Value = 0 to 4095, Physical = Value x 302 / 1365 in 10⁻² inch units
  uint16_t DIG_TouchScreenFingerAzimuth;             // Usage 0x000D003F: Azimuth, Value = 0 to 62831, Physical = Value in 10⁻⁴ rad units
  uint8_t  DIG_TouchScreenFingerTipSwitch_1 : 1;     // Usage 0x000D0042: Tip Switch, Value = 0 to 1, Physical = Value x 62831 in 10⁻⁴ rad units
  uint8_t  : 7;                                      // Pad
  uint8_t  DIG_TouchScreenFingerContactIdentifier_1; // Usage 0x000D0051: Contact Identifier, Value = 0 to 1, Physical = Value x 62831 in 10⁻⁴ rad units
  uint16_t GD_TouchScreenFingerX_1[2];               // Usage 0x00010030: X, Value = 0 to 4095, Physical = Value x 241 / 819 in 10⁻² inch units
  uint16_t GD_TouchScreenFingerY_1[2];               // Usage 0x00010031: Y, Value = 0 to 4095, Physical = Value x 302 / 1365 in 10⁻² inch units
  uint16_t DIG_TouchScreenFingerWidth_1;             // Usage 0x000D0048: Width, Value = 0 to 4095, Physical = Value x 302 / 1365 in 10⁻² inch units
  uint16_t DIG_TouchScreenFingerHeight_1;            // Usage 0x000D0049: Height, Value = 0 to 4095, Physical = Value x 302 / 1365 in 10⁻² inch units
  uint16_t DIG_TouchScreenFingerAzimuth_1;           // Usage 0x000D003F: Azimuth, Value = 0 to 62831, Physical = Value in 10⁻⁴ rad units
                                                     // Collection: CA:TouchScreen
  uint16_t DIG_TouchScreenRelativeScanTime;          // Usage 0x000D0056: Relative Scan Time, Value = 0 to 65535, Physical = Value in 10⁻⁴ s units
  uint8_t  DIG_TouchScreenContactCount;              // Usage 0x000D0054: Contact Count, Value = 0 to 127, Physical = Value x 65535 / 127 in 10⁻⁴ s units
} inputReport01_t;

符合HID的触摸屏包数据结构

HID-compliant touch screen packet data structure

c

embedded

usb

hid

embedded-linux