@siam There actually are mode code coming out of the M122, but was marked as spam by the forum so I cannot post them here...

@phaedrux Yes my external driver needs 5V, will this breakout board work for my case?
https://duet3d.dozuki.com/Wiki/Duet_Expansion_Breakout_Board

@phaedrux Since I'll use the E2 of the expansion to wire my extruder motor, how to modify the config code to use the E2? I won't use the E0 and E1.

My config.g Driver code is below:

; Drives
M569 P0 S0 ; physical drive 0 goes backwards
M569 P1 S0 ; physical drive 1 goes backwards
M569 P2 S1 ; physical drive 2 goes forwards
M584 X0 Y1 Z2 ; set drive mapping
M350 X16 Y16 Z16 I1 ; configure microstepping with interpolation
M92 X80.00 Y80.00 Z400.00 ; set steps per mm
M566 X900.00 Y900.00 Z60.00 ; set maximum instantaneous speed changes (mm/min)
M203 X6000.00 Y6000.00 Z180.00 ; set maximum speeds (mm/min)
M201 X500.00 Y500.00 Z20.00 ; set accelerations (mm/s^2)
M906 X800 Y800 Z800 I30 ; set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

@phaedrux I'm not using motor drive output, I'm using the expansion portion of the board, which is 3.3V output. But my extruder motor needs 5V.

@phaedrux Hi, my extruder motor needs 5V, while the Duet board output is 3.3V, I'm thinking of buying a breakout board like this:
https://duet3d.dozuki.com/Wiki/Duet_Expansion_Breakout_Board
Will it work?

@phaedrux Could you please explain how to do that?

Hi, now the temperature is all set, but I have some problems with the extruder motor. I used the expansion portion (highlighted in the red square shown below) of the board for extruder signals. The channels I connected are E2, but I couldn't setup the config file to use the E2 motor because it isn't listed.

@phaedrux I plan to use a dual thermocouple connector to split the thermocouple signal, so that one goes to the PID and the other goes to the Duet board.

@phaedrux It's a very common Inkbird PID controller. The thermocouple from the extruder head is a K-type thermocouple.

@phaedrux I want to send the temperature signal from PID to the Duet board, do I need adapters to do it? I saw online there's some kind of daughter board for thermocouple. I'm using Duet 2 ethernet, which daughter board should I purchase?

@phaedrux Another question I have is: what is the unit of the numbers in the machine movement control? Is it mm?