Can I build USBtinyISP onto Atmega32U4?

[smorehou]

Weird. Ok, thanks. I think I've got all the parts to build a BB+ so I'll try that.

[philba]

Sorry, I missed the fact that you ordered a Teensy in your OP. Teensy boards work for me in every other use but this one. I first got the AVRISP working on an Adafruit 32u4 board, and it works fine. Then I tried a Teensy. Not so much working. I would think that if it were a 32u4 problem, my adafruitU4 would have had the problem also. I've also loaded a recompiled version on a couple of cheap 32u2 boards with not problem (not bad for a $15 programmer). I worked on the Teensy problem for a while, and got it down to a problem with the /RESET line not staying low during programming. I gave up when I realized that my original Adafruit board still worked, so just used that.

Interesting. Is this because of the bootloader in the teensy? At $16 a pop, the teensy is my goto board for small projects.

[abqlewis]

Interesting. Is this because of the bootloader in the teensy? At $16 a pop, the teensy is my goto board for small projects.

I don't know for sure, but the bootloader was my first WAG. I even bought a second Teensy (figured I would still be able to use it for anything else either way) to make sure, and sure enough, it has the same problem. Even though I suspect the bootloader, I haven't removed it from either Teensy. I don't really know how to reload it, or even if I can.
There are references out there of people that have hardware and code for a Teensy programmers. I just never got around to hunting them down, and asking questions. Again, my AdafruitU4 just works, and I have plenty for the Teensy(s) to do.

[smorehou]

As far as I can tell, you can't get the Teensy code back onto the chip if you overwrite it with something else. Its proprietary and protected.

[smorehou]

Success! Thanks so much for your help and for tipping me off that the Teensy could be my issue. That was the case. I have no idea what's special about the Teensy that caused this problem (and neither does the maker of the Teensy, who offered me very limited support before blaming it on the 'overly-complex' [paraphrase] LUFA project) and I suppose at this point, I don't really care. I'll find another use for the Teensy I'm sure.

I would have preferred the Breakout Board sold here at Adafruit, but I didn't find this site until about 10 minutes after I bought the Teensy direct.

Still, my Franken-board version of the Breakout Board worked just fine! I was able to put the LUFA avrispmkII project onto the board no problem, and it worked beautifully! Yay!

- Steven