Cat, I think a zener would need to be a mighty one to prevent spikes from a PSU that can provide maybe 15-30A. Current limit resistor first (300ma if I remember), then zener. The rest of it is curiosity, I'm more interested in how the SPI ONLY gets stuck under certain power conditions then try to fix it, so I may never will. Understandable... Regards, Mike [Non-text portions of this message have been removed]
Message
Re: [AVR-Chat] Code stuck waiting for SPI transmission but only after power-up. (ATMega644P)
2010-03-12 by Mike