2013-03-29 59 views
2

我有一個HID設備(picoLCD單色顯示屏),我在用C#編寫的Windows程序中打開。 我得到我的設備的3 HID「實例」具有以下路徑:什麼是USB HID col參數

_devicePath = "\\\\?\\hid#vid_04d8&pid_c002&col01#7&12adec39&0&0000#{4d1e55b2-f16f-11cf-88cb-001111000030}" 
_devicePath = "\\\\?\\hid#vid_04d8&pid_c002&col02#7&12adec39&0&0001#{4d1e55b2-f16f-11cf-88cb-001111000030}" 
_devicePath = "\\\\?\\hid#vid_04d8&pid_c002&col03#7&12adec39&0&0002#{4d1e55b2-f16f-11cf-88cb-001111000030}" 

它們都具有相同的VID和PID,但不同的「關口」。這個參數是什麼意思? 爲什麼有一個設備有3個設備「描述符」?

USBVIEW僅示出一個與2個端點物理設備:

Device Descriptor: 
bcdUSB:    0x0200 
bDeviceClass:   0x00 
bDeviceSubClass:  0x00 
bDeviceProtocol:  0x00 
bMaxPacketSize0:  0x08 (8) 
idVendor:   0x04D8 (Microchip Technology Inc.) 
idProduct:   0xC002 
bcdDevice:   0x0002 
iManufacturer:  0x01 
iProduct:    0x02 
iSerialNumber:  0x03 
bNumConfigurations: 0x01 

ConnectionStatus: DeviceConnected 
Current Config Value: 0x01 
Device Bus Speed:  Full 
Device Address:  0x05 
Open Pipes:    2 

Endpoint Descriptor: 
bEndpointAddress:  0x81 IN 
Transfer Type: Interrupt 
wMaxPacketSize:  0x0040 (64) 
bInterval:   0x01 

Endpoint Descriptor: 
bEndpointAddress:  0x01 OUT 
Transfer Type: Interrupt 
wMaxPacketSize:  0x0040 (64) 
bInterval:   0x01 

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