Support for ATmega8/16/32U series wanted

[elosha]

These are newer AVR microcontrollers with integrated USB. Well, not so new, as Arduino Leonardo uses an ATmega32U4.

Series includes at least:

• ATmega8U2 – id 0x1E9389
• ATmega16U2 – id 0x1E9489
• ATmega32U2 – id 0x1E958A
• ATmega16U4 – id 0x1E9488
• ATmega32U4 – id 0x1E9587
• ATxmega16A4U – id 0x1E9441
• ATxmega32A4U – id 0x1E9541
• ATxmega64A4U – id 0x1E9646
• ATxmega128A4U – id 0x1E9746

Datesheets are here:

• ATmega*U2
• ATmega*U4
• ATxmega*A4U – file size 24MB!

I will look into the datasheets next days if the programming scheme resembles some existent devices.

[elosha]

I checked the datasheets in meanwhile.

1. U2 devices seem to be drop-in compatible to ATmega88/168/328. Copying device entries with modified id bytes could work, I will order some ICs for verification. Or if a contributor already has those U series devices at hand, they're invited to do the experiment first ;)

2. U4 devices are a new development centered around the USB feature, higher pin count than ATmega*8 series, available only as TQFP44 or QFN44 package. So there's an adapter needed, which I don't have, and it's probably a matter of sniffing the official Windows tool – help is needed here.

By the way: Who knows the exact difference between protocol 0x71 and 0x73? Are they completely divergent … or is 0x73 just newer, like an update for more recent products?