Bed temp sensor issues

[rmriggin]

My Duet .6 running 1.22 is reporting a temp of 90C with or without a sensor connected. The MCU temp reported is around 32 C which is more in line with ambient temp and what the bed typically would report when I have used other boards (RAMPS 1.6/Marlin 1.1.9, MKS SBASE 1.4). So it appears there is an issue with the thermistor input for bed but I have no idea of how to troubleshoot/test that theory.

[dc42]

I think that either you have bad values in your M305 P0 command in config.g, or the ADC input for the bed thermistor is damaged. The Duet 0.6 didn't have the same input protection that later Duets have.

Does the hot end thermistor input work properly?

[rmriggin]

@dc42 the hotend temp reads lower than it should currently sitting in room where ambient is about 68F it's reading at 0 to -1-2 C. I used the default values for the firmware thermistor config at the duet firmware config page. The bed temp sensor values are between 80-90C regardless of whether there is a sensor connected or not. When sensor is disconnected for hotend it reads the expected 2000F.