As Nicholas Flowers wrote: > Also, my understanding (which may be wrong) is that USB considers IN 2 > distinct from OUT 2, but that the 16U2 (at least) doesn't allow you to both > configure IN 2 and OUT 2. I could have an IN 1/OUT 2 or vice versa.
That's exactly the LUFA problem I mentioned. USB considers endpoints 0x02 and 0x82 being two distinct EPs (one OUT, one IN), and that's what the old Philips/NXP PDIUSBD12 chip on the AVRISPmkII does. However, Atmel controllers don't support this, they require the IN and OUT endpoint numbers being distinct in the lower 7 bits. Since the LUFA implementation wants to be Atmel Studio compliant, they then switch the endpoint direction dynamically, but that's tricky. -- cheers, Joerg .-.-. --... ...-- -.. . DL8DTL http://www.sax.de/~joerg/ Never trust an operating system you don't have sources for. ;-) _______________________________________________ avrdude-dev mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/avrdude-dev
