Hi all I am new to USB and keil after studying keil Hid example and lots of forum posts,I modified the code to make it as I need. Now I am able to send 64 byte of code to\from PC from\to my device. The problem is that I can do it with USB_EVT_IN event but when I want to use USB_EVT_OUT the device sends nothing to host.the description is ok(tested with USBlyzer). another thing: I am a little bit confused about what are EPx IN\OUT really are, any lightening idea will be appreciated. finally,wanted to thank Tsuneo for all his great work in this area,his posts helped me and surely so many others,alot. Regards, Hessam
> but when I want to use USB_EVT_OUT the device sends nothing to host.
USB naming convention is host-centric. - Host sends data to OUT endpoint on a device. - Host receives data from IN endpoint on a device.
While you are coding device firmware, you'll have odd feeling until you are familiar with this convention.
On the device side, - USB_EVT_OUT event occurs when a packet has been received from host. - USB_EVT_IN event is invoked after a packet has sent to host.
Tsuneo