Thanks in Advance. I am using keil HID example and win-api to make a usb hid device for sending and receiving data using interrupt transfer. I define the package size as 64 bytes, and of cause if the data sended by the device less than 64 bytes, the host(Overlapped mode) will come up with a timeout error. And I do search in the forum, everybody says I should send a ZLP(zero length package), but I could not find any detail about what ZLP real is, and how to send a ZLP by the device or by the host. So I will appreciate if anybody tell me what can I do. Forgive my fool. Thanks again.
"HID report" is general term, which collects input / output / feature reports.
The report type is determined by the place where the report passes. Interrupt IN endpoint - input report Interrupt OUT endpoint - output report EP0 IN (Get_Report request) - input / feature report EP0 OUT (Set_Report request) - output / feature report
Tsuneo