by, maybe, grounding a HIGH output ? I have a PCB with an Atmega88PA MCU and an ADS114S06 ADC that both share three SPI lines (SCK, MISO, MOSI). I was trying to program the MCU (via SPI interface), it responded with its device signature OK, but then verifying the flashed program would fail on byte 0. Thinking that the ADC is the culprit I thought "why not tie its !RESET line to GND so that it (presumably) tri-states its IO pins ?". Done just that a couple of times, still the same outcome. Then I have probably shorted out some other output pins on the MCU with the loose GND wire... and the Atmega88PA started giving out 0x000000 as device signature. So, any way to revive it ? What about the conflicting SPI devices, what is the proper way to deal with them ? I currently have 47 ohms on all signal lines between the MCU and ADC, including the SPI lines (as shown in the datasheet above). Thank you!