At the moment I am happy and sad as well. The happy part is that I managed to program the Atmel chip. The downside is that I think I also blew up one chip. The Chip identification (which worked before) does not give me any values anymore. I can take a new one and try again, but that one can be blown up too 🙁 I need to find out what has happened here.
Also when I want to verify the content of the chip, I get probems with the shift register. There are specific values which are not ransferred correctly. This is something I cannot explain at all. I have the shift register split up in 2 IC’s, but exchanging them does not make a difference.
I will try next time to get the microcontroller connected to the serial memory chip and connect it to the keyboard. I will let you know the results of that.