OK, I give up..... has anyone got any experiance of handling interrupt transfers using the microchip USB framework code, USB18.asm etc.

I have been reading through the files (on and off for 2 weeks), trying to break them down, but the framework seems to be geared only for EP0 std requests, HID and CDC stuff but not interrupt transfers.

My device enumerates fine and I was able to re-write some of the assembler to reply to a specific class request, but this last part is killing me.
All I have left is to be able to detect an EP1_IN interrupt request and send 7 bytes back to the host via EP1_IN.

I am interfacing to existing software (process monitorring) so have no control over the host side of things.

Some pointers in the right direction, thoughts, ideas or a link to another framework that can handle interrupt transfers would be great.

Thanks Paul