我创建了自己的可配置键盘设备（我可以更改任何键的代码）。 现在我正在尝试编写将与此设备通信的C＃应用程序，但我对此有疑问。
键盘设备报告描述符：
//Keyboard
0x05, 0x01, // USAGE_PAGE (Generic Desktop)
0x09, 0x06, // USAGE (Keyboard)
0xa1, 0x01, // COLLECTION (Application)
0x85, 0x01, // REPORT_ID (1)
0x05, 0x07, // USAGE_PAGE (Keyboard)
0x19, 0xe0, // USAGE_MINIMUM (Keyboard LeftControl)
0x29, 0xe7, // USAGE_MAXIMUM (Keyboard Right GUI)
0x15, 0x00, // LOGICAL_MINIMUM (0)
0x25, 0x01, // LOGICAL_MAXIMUM (1)
0x75, 0x01, // REPORT_SIZE (1)
0x95, 0x08, // REPORT_COUNT (8)
0x81, 0x02, // INPUT (Data,Var,Abs)
0x95, 0x01, // REPORT_COUNT (1)
0x75, 0x08, // REPORT_SIZE (8)
0x81, 0x03, // INPUT (Cnst,Var,Abs)
0x95, 0x05, // REPORT_COUNT (5)
0x75, 0x01, // REPORT_SIZE (1)
0x05, 0x08, // USAGE_PAGE (LEDs)
0x19, 0x01, // USAGE_MINIMUM (Num Lock)
0x29, 0x05, // USAGE_MAXIMUM (Kana)
0x91, 0x02, // OUTPUT (Data,Var,Abs)
0x95, 0x01, // REPORT_COUNT (1)
0x75, 0x03, // REPORT_SIZE (3)
0x91, 0x03, // OUTPUT (Cnst,Var,Abs)
0x95, 0x06, // REPORT_COUNT (6)
0x75, 0x08, // REPORT_SIZE (8)
0x15, 0x00, // LOGICAL_MINIMUM (0)
0x25, 0xFF, // LOGICAL_MAXIMUM (255) //0x25, 0x65, // LOGICAL_MAXIMUM (101)
0x05, 0x07, // USAGE_PAGE (Keyboard)
0x19, 0x00, // USAGE_MINIMUM (Reserved (no event indicated))
0x29, 0x65, // USAGE_MAXIMUM (Keyboard Application)
0x81, 0x00, // INPUT (Data,Ary,Abs)
0xc0, // END_COLLECTION
/*65*/
//Device Configuration
0x06, 0xFF, 0xA0, // USAGE_PAGE (Vendor-Defined)
0x09, 0x01, // USAGE (Vendor-Defined)
0xA1, 0x01, // COLLECTION (Application)
0x85, 0x02, // REPORT_ID (2)
0x09, 0x03, // USAGE (Vendor-Defined)
0x15, 0x00, // LOGICAL_MINIMUM (0)
0x26, 0x00, 0xFF, // LOGICAL_MAXIMUM (255)
0x95, 0x2D, // REPORT_COUNT (45)
0x75, 0x08, // REPORT_SIZE (8)
0x81, 0x02, // Input (Data, Variable, Absolute)
0x09, 0x04, // USAGE (Vendor-Defined)
0x15, 0x00, // LOGICAL_MINIMUM (0)
0x26, 0x00, 0xFF, // LOGICAL_MAXIMUM (255)
0x95, 0x2D, // REPORT_COUNT (45)
0x75, 0x08, // REPORT_SIZE (8)
0x91, 0x02, // Output (Data, Variable, Absolute)
0x09, 0x05, // USAGE (Vendor-Defined)
0x15, 0x00, // LOGICAL_MINIMUM (0)
0x26, 0x00, 0xFF, // LOGICAL_MAXIMUM (255)
0x95, 0x2D, // REPORT_COUNT (45)
0x75, 0x08, // REPORT_SIZE (8)
0xB1, 0x02, // Feature (Data, Variable, Absolute)
0xc0, // END_COLLECTION
C＃代码的一部分（我使用HIDLibrary）：
Device = HidDevices.Enumerate(VendorID, ProductID).FirstOrDefault();
if (Device == null)
{
return;
}
//Open Device
Device.OpenDevice();
//if( Device.IsOpen == false )
// return;
Device.Inserted += DeviceAttachedHandler;
Device.Removed += DeviceRemovedHandler;
Device.MonitorDeviceEvents = true;
//Handle Reports
KeyMapRequest(); //Fill Buffer with KeyMapRequest
HidReport report = Device.CreateReport();
report.ReportId = 2;
report.Data = USBBuffer;
succeed = Device.WriteReport(report, 10);
Device.ReadReport(OnReport);
LastDataEventDate = DateTime.Now;
while ((DateTime.Now - LastDataEventDate).TotalMilliseconds < 100)
{
}
键盘工作正常，但应用程序无法与设备通信。 ＆＃34; Device.IsOpen＆＃34;总是＆＃34;假＆＃34;。 但是当我从报告描述符部分删除＆＃34; Report_ID（1）＆＃34; （键盘部分），＆＃34; Device.IsOpen＆＃34;是＆＃34;是＆＃34;，沟通正常。
Windows是否负责阻止通信？我该怎么处理？ 或许我在描述符中有一些错误？
答案 0 :(得分：0)
我认为这种行为可能是LOGICAL_MAXIMUM规范不正确的副作用。您不小心编码了-256而不是255.当我使用hidrdd解码您的声明时，它会输出：
/*
06 FFA0 (GLOBAL) USAGE_PAGE 0xA0FF Reserved
09 01 (LOCAL) USAGE 0xA0FF0001
A1 01 (MAIN) COLLECTION 0x01 Application (Usage=0xA0FF0001: Page=Reserved, Usage=, Type=) <-- Warning: USAGE type should be CA (Application)
85 02 (GLOBAL) REPORT_ID 0x02 (2)
09 03 (LOCAL) USAGE 0xA0FF0003
15 00 (GLOBAL) LOGICAL_MINIMUM 0x00 (0) <-- Redundant: LOGICAL_MINIMUM is already 0
26 00FF (GLOBAL) LOGICAL_MAXIMUM 0xFF00 (-256)
95 2D (GLOBAL) REPORT_COUNT 0x2D (45) Number of fields
75 08 (GLOBAL) REPORT_SIZE 0x08 (8) Number of bits per field <-- Redundant: REPORT_SIZE is already 8
81 02 (MAIN) INPUT 0x00000002 (45 fields x 8 bits) 0=Data 1=Variable 0=Absolute 0=NoWrap 0=Linear 0=PrefState 0=NoNull 0=NonVolatile 0=Bitmap <-- Error: REPORT_SIZE (8) is too small for LOGICAL_MAXIMUM (-256) which needs 9 bits. <-- Error: LOGICAL_MAXIMUM (-256) is less than LOGICAL_MINIMUM (0)
09 04 (LOCAL) USAGE 0xA0FF0004
15 00 (GLOBAL) LOGICAL_MINIMUM 0x00 (0) <-- Redundant: LOGICAL_MINIMUM is already 0
26 00FF (GLOBAL) LOGICAL_MAXIMUM 0xFF00 (-256) <-- Redundant: LOGICAL_MAXIMUM is already -256
95 2D (GLOBAL) REPORT_COUNT 0x2D (45) Number of fields <-- Redundant: REPORT_COUNT is already 45
75 08 (GLOBAL) REPORT_SIZE 0x08 (8) Number of bits per field <-- Redundant: REPORT_SIZE is already 8
91 02 (MAIN) OUTPUT 0x00000002 (45 fields x 8 bits) 0=Data 1=Variable 0=Absolute 0=NoWrap 0=Linear 0=PrefState 0=NoNull 0=NonVolatile 0=Bitmap <-- Error: REPORT_SIZE (8) is too small for LOGICAL_MAXIMUM (-256) which needs 9 bits. <-- Error: LOGICAL_MAXIMUM (-256) is less than LOGICAL_MINIMUM (0)
09 05 (LOCAL) USAGE 0xA0FF0005
15 00 (GLOBAL) LOGICAL_MINIMUM 0x00 (0) <-- Redundant: LOGICAL_MINIMUM is already 0
26 00FF (GLOBAL) LOGICAL_MAXIMUM 0xFF00 (-256) <-- Redundant: LOGICAL_MAXIMUM is already -256
95 2D (GLOBAL) REPORT_COUNT 0x2D (45) Number of fields <-- Redundant: REPORT_COUNT is already 45
75 08 (GLOBAL) REPORT_SIZE 0x08 (8) Number of bits per field <-- Redundant: REPORT_SIZE is already 8
B1 02 (MAIN) FEATURE 0x00000002 (45 fields x 8 bits) 0=Data 1=Variable 0=Absolute 0=NoWrap 0=Linear 0=PrefState 0=NoNull 0=NonVolatile 0=Bitmap <-- Error: REPORT_SIZE (8) is too small for LOGICAL_MAXIMUM (-256) which needs 9 bits. <-- Error: LOGICAL_MAXIMUM (-256) is less than LOGICAL_MINIMUM (0)
C0 (MAIN) END_COLLECTION Application
*/
在HID报告描述符中，您需要以Little-Endian顺序编码值。这也适用于USAGE_PAGE（我已经更正了下面的例子）。
顺便说一下，您不需要重复LOGICAL_MINIMUM，LOGICAL_MAXIMUM，REPORT_COUNT或REPORT_SIZE值，因为它们都是GLOBAL项 - 因此只有在值改变时（因为解析器扫描它们）才需要指定它们。尝试指定：
/*
06 A0FF (GLOBAL) USAGE_PAGE 0xFFA0 Vendor-defined
09 01 (LOCAL) USAGE 0xFFA00001
A1 01 (MAIN) COLLECTION 0x01 Application (Usage=0xFFA00001: Page=Vendor-defined, Usage=, Type=)
85 02 (GLOBAL) REPORT_ID 0x02 (2)
09 03 (LOCAL) USAGE 0xFFA00003
15 00 (GLOBAL) LOGICAL_MINIMUM 0x00 (0) <-- Redundant: LOGICAL_MINIMUM is already 0
26 FF00 (GLOBAL) LOGICAL_MAXIMUM 0x00FF (255)
95 2D (GLOBAL) REPORT_COUNT 0x2D (45) Number of fields
75 08 (GLOBAL) REPORT_SIZE 0x08 (8) Number of bits per field <-- Redundant: REPORT_SIZE is already 8
81 02 (MAIN) INPUT 0x00000002 (45 fields x 8 bits) 0=Data 1=Variable 0=Absolute 0=NoWrap 0=Linear 0=PrefState 0=NoNull 0=NonVolatile 0=Bitmap
09 04 (LOCAL) USAGE 0xFFA00004
91 02 (MAIN) OUTPUT 0x00000002 (45 fields x 8 bits) 0=Data 1=Variable 0=Absolute 0=NoWrap 0=Linear 0=PrefState 0=NoNull 0=NonVolatile 0=Bitmap
09 05 (LOCAL) USAGE 0xFFA00005
B1 02 (MAIN) FEATURE 0x00000002 (45 fields x 8 bits) 0=Data 1=Variable 0=Absolute 0=NoWrap 0=Linear 0=PrefState 0=NoNull 0=NonVolatile 0=Bitmap
C0 (MAIN) END_COLLECTION Application
*/