PolkaDot:
How do you have the unused pin configured? Mine is tied to ground, though I get different results with it tied to Vcc. The datasheet doesn't specify which is best, though it advises not to leave it floating.23LC512 pin 1 CS to UNO pin 10 (CS)
23LC512 pin 2 SO to UNO pin 12 (MISO) or(pin 1 of ICSP bus)
23LC512 pin 3 to GND
23LC512 pin 4 to GND
23LC512 pin 5 SI to UNO pin 11 (M0S1) or (pin 4 of ICSP bus)
23LC512 pin 6 SCK to UNO pin 13 (SCK) or (pin 3 of ICSP bus)
23LC512 pin 7 to Vcc
23LC512 pin 8 to Vcc
I'll try rewiring mine with shorter jumpers.. maybe it's noise or there's too much capacitance on the line? I'm going to try observing the SCK signal on my o-scope later, some devices are sensitive to long rise-times. On a preliminary search, I couldn't find any free samples for Schmitt triggers..I also got better results when I slowed down my serial port - I went from 115200 down to 38600 and didn't seem to find a fail
As for tracking data, I'm vaguely thinking of using it as a type of data buffer between MCUs, so that one isn't stuck waiting for the other to free up. Effectively it'd be structured as a stack, with a header byte saying how many bytes and of what type it should be expecting.
Actually, I think it might be better to write 64K of 0xAA and then go back an read all 64K to find a fail - can't trust the serial output