Hello,
I'm developing a USB firmaware for LPC2378 based on the KEIL HID example. In a first step I've changed the report size to 64 Byte and added an out_endpoint as descriped in this thread: http://www.keil.com/forum/docs/thread11137.asp
Now I want to realize this procedure: The Application on the MCB2300 sends data to a USB-Buffer. Every 20 ms this Buffer has to be send to the host. If the Buffer is full before reaching the dealdine of 20 ms it is also send to the host. My problem is, that I need to send Messages of variable Size from the MCB2300 to the host. Is it possible to reach this aim with HID Example?
So if I only want to send 40 bytes after the deadline the MCB2300 will create an in_report with 64 bytes (40 bytes payload + 24 bytes padding). Now the host application interprets the whole in-report erroneously. On the other hand the host software can send data of variable lenght to the MCB2300. But al the data will be packed in 64 byte reports. So how can my firmware differentiate between payload and padding bytes?
Thanks for your help, Thomas