Another Temp daughterboard problem

larrylf

I'm in the process of setting up a printer with a duet3 mini 5+. I have the temperature daughterboard for it, and am tried to set it up in my config file.
From the documentation, it looks like I should use M308:
M308 S3 Y"thermistor" P"spi.cs1" T100000 B4138

But when it boots up, I get an error "pin spi.cs1 doesn't support analog input"
What am I doing wrong?

Phaedrux

@larrylf said in Another Temp daughterboard problem:

I have the temperature daughterboard for it

Can you be more specific? Is it a PT100 or thermocouple daughterboard?

https://docs.duet3d.com/en/Duet3D_hardware/Accessories/PT100_Temperature_Daughterboard

https://docs.duet3d.com/en/Duet3D_hardware/Accessories/Thermocouple_Daughterboard

dc42

@larrylf the Y parameter in your M308 command is wrong. The sensor is not a thermistor.

larrylf

@phaedrux Sorry, it is the PT100 board, and I am using a thermistor in it.

larrylf

@dc42 Oh, so you're saying that I have to identify it as the board, not what its used for?
I'll try to find what it should be, then

larrylf

@larrylf yes, that worked - thank you

droftarts

@larrylf you are not going to get accurate temperatures using a thermistor with the PT100 board. As temperature increases, a thermistor’s resistance decreases; a PT100’s resistance increases. So a thermistor connected to the PT100 board will report a drop in temperature as temperature increases.

You can connect a thermistor or PT1000 directly to the temperature inputs on the Duet; you don’t need a daughterboard.

Ian

larrylf

@droftarts yes, the thermistor was a mistake - in fact, I seem to have the wrong sensors everwhere (PT100's in the mainboard TEMP, thermistor in the daughterboard).
Fixed now, but frustrating...