USB键盘报告描述符数据格式分析

USB键盘的HID报表描述符的内容参见下表。数据的输入端点为中断方式，当有键盘敲击事件时，会上报数据长度为8字节的数据报告。

0x05,0x01,// Global Generic Desktop
0x09,0x06,// Local KeyBoard 
0xA1,0x01,// Main app collection
0x05,0x07,// Global KeyBoard

//第1字节
0x19,0xe0,// Local Usage Min (KeyBoard LeftControl)
0x29,0xe7,// Local Usage Max (KeyBoard Right GUI)
0x15,0x00,// Global Logical Min
0x25,0x01,// Global Logical Max 
0x95,0x08,// Global ReportCount
0x75,0x01,// Global ReportSize
0x81,0x02,// Main Input(Data,Var,Abs)

//第2字节
0x95,0x01,// Global ReportCount
0x75,0x08,// Global ReportSize
0x81,0x03,// Main Input(Cnst,Var,Abs)

//第3-8字节
0x95,0x06,// Global ReportCount
0x75,0x08,// Global ReportSize
0x15,0x00,// Global Logical Min
0x26,0xff,0x00,//Global Logical Max
0x19,0x00,// Local Usage Min
0x29,0x65,// Local Usage Max
0x81,0x00,// Main Output(Data,Ary,Abs)

//1字节输出报告
0x15,0x00,// Global Logical Min
0x25,0x01,// Global Logical Max
0x95,0x05,// Global ReportCount
0x75,0x01,// Global ReportSize
0x05,0x08,// Global LED
0x19,0x01,// Local Usage Min
0x29,0x05,// Local Usage Max
0x91,0x02,// Main Output(Data,Var,Abs)

//补足上面变成1个字节
0x95,0x01,// Global ReportCount
0x75,0x03,// Global ReportSize
0x91,0x03,// Main Output(Cnst,Var,Abs)
0xc0      // Main End collection

键盘的描述符共有8字节的输入报告和1字节的输出报告。

1字节的输出报告输出报告

如果不给键盘配置OUT端点，那么键盘的1字节输出报告将由控制端点的SetReport进行传输。
1字节输出报告：这1个字节总共用了5bits使用3bits常量来补足成1个字节。5bits用来点亮特殊键盘上的Led灯，比如键盘的大小写，数字键，小键盘的LED灯。

8字节的输入报告

数据报告8个字节的含义见下表：

• Byte0各位则表示左右GUI(win),alt，shift，control键是否按下，按下为1。
• Byte1是保留字节，
• 其6个字节表示此时按下的其他所有键盘按键的键码，从低到高填充，没按就是0x00.如果同时按下的键超过允许，则显示0xff

Byte0各位则表示左右GUI(win),alt，shift，control键是否按下，按下为1。

键码含义可参照《HID Usage Tables》Version 1.11第53页中的K10 eyboard/Keypad Page。

附Keyboard Page Usage

文档HID Usage Tables详见：https://d1.amobbs.com/bbs_upload782111/files_47/ourdev_692986N5FAHU.pdf

#define        KB_ERROR            0x01
#define        KB_A                0x04
#define        KB_B                0x05
#define        KB_C                0x06
#define        KB_D                0x07
#define        KB_E                0x08
#define        KB_F                0x09
#define        KB_G                0x0A
#define        KB_H                0x0B
#define        KB_I                0x0C
#define        KB_J                0x0D
#define        KB_K                0x0E
#define        KB_L                0x0F
#define        KB_M                0x10
#define        KB_N                0x11
#define        KB_O                0x12
#define        KB_P                0x13
#define        KB_Q                0x14
#define        KB_R                0x15
#define        KB_S                0x16
#define        KB_T                0x17
#define        KB_U                0x18
#define        KB_V                0x19
#define        KB_W                0x1A
#define        KB_X                0x1B
#define        KB_Y                0x1C
#define        KB_Z                0x1D
#define        KB_1                0x1E
#define        KB_2                0x1F
#define        KB_3                0x20
#define        KB_4                0x21
#define        KB_5                0x22
#define        KB_6                0x23
#define        KB_7                0x24
#define        KB_8                0x25
#define        KB_9                0x26
#define        KB_0                0x27
#define        KB_ENTER            0x28
#define        KB_ESC                0x29
#define        KB_BACKSPACE        0x2A
#define        KB_TAB                0x2B
#define        KB_SPACE            0x2C
#define        KB_MIUS                0x2D    //-_
#define        KB_EQUAL            0x2E    //=+
#define        KB_LSQUBRACKET        0x2F    //[{
#define        KB_RSQUBRACKET        0x30    //]}
#define        KB_BACKSLASH        0x31    //\|

#define        KB_SEMICOLON        0x33    //;:
#define        KB_APOSTROPHE        0x34    //'"
#define        KB_TILDE            0x35    //`~
#define        KB_COMMA            0x36    //,<
#define        KB_FULLSTOP            0x37    //.>
#define        KB_SLASH            0x38    ///?
#define        KB_CAPSLOCK            0x39   
#define        KB_F1                0x3A
#define        KB_F2                0x3B
#define        KB_F3                0x3C
#define        KB_F4                0x3D
#define        KB_F5                0x3E
#define        KB_F6                0x3F
#define        KB_F7                0x40
#define        KB_F8                0x41
#define        KB_F9                0x42
#define        KB_F10                0x43
#define        KB_F11                0x44
#define        KB_F12                0x45
#define        KB_PRTSCR            0x46
#define        KB_SCOLLLOCK        0x47
#define        KB_PAUSE            0x48
#define        KB_INSERT            0x49
#define        KB_HOME                0x4A
#define        KB_PAGEUP            0x4B
#define        KB_DELETE            0x4C
#define        KB_END                0x4D
#define        KB_PAGEDOWN            0x4E
#define        KB_RARROW            0x4F
#define        KB_LARROW            0x50
#define        KB_DARROW            0x51
#define        KB_UARROW            0x52
#define        KB_NUMLOCK            0x53
#define        KB_PAD_DIV            0x54    ///
#define        KB_PAD_MUL            0x55    //*
#define        KB_PAD_MINUS        0x56    //-
#define        KB_PAD_PLUS           0x57    //+
#define        KB_PAD_ENTER        0x58
#define        KB_PAD_1            0x59
#define        KB_PAD_2            0x5A
#define        KB_PAD_3            0x5B
#define        KB_PAD_4            0x5C
#define        KB_PAD_5            0x5D
#define        KB_PAD_6            0x5E
#define        KB_PAD_7            0x5F
#define        KB_PAD_8            0x60
#define        KB_PAD_9            0x61
#define        KB_PAD_0            0x62
#define        KB_PAD_DEL           0x63
#define        KB_APPLICATION        0x65    //RWin右边键
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