M915: Configure motor stall detection

R006

I am using a Duet 3 board with three Z-axis stepper motors connected. If any motor connector becomes disconnected, a warning message appears:
"Driver 0.4 Phase A or B may be disconnected."
**I would like to implement code that automatically performs the following actions when this warning is triggered:

Immediately disable all motors.
Display the message: "Please check Z motor connection."**

I have tried using stall detection and created a driver-warning.g file with the following command:
M915 Z0.2:0.4:0.5 S2 R3
However, this approach did not work as expected. I am testing this on a table-top setup.

@dc42 @Phaedrux

dc42

@R006 stall detection is not relevant to detecting open-load conditions, however the driver-warning.g file should catch it if you are running a sufficiently recent version of RRF.

R006

@dc42
I am currently using RepRapFirmware version 3.6.0rc1 and testing it on a table-top setup.
Could you please provide an example of a driver-warning file for reference?

droftarts

@R006 said in M915: Configure motor stall detection:

M915 Z0.2:0.4:0.5 S2 R3

I think this should be either M915 Z S2 R3 or M915 P0.2:0.4:0.5 S2 R3 to enable stall detection. Check it is configured correctly by sending M915 on it's own.

EDIT2: Sorry, I overlooked that phase disconnection IS mentioned as a driver warning, not a driver error.

According to https://docs.duet3d.com/User_manual/RepRapFirmware/Events#events it is 'driver error' that is triggered for phase disconnection, not driver warning:
(EDIT: sorry, phase disconnection is not mentioned in the driver error section, but I would think it does count as a 'driver error' rather than 'driver warning'.)

~~Driver error (e.g. over temperature shutdown, short-to-ground, or closed loop driver position difference error limit exceeded)~~

The default behaviour is to "Pause print without running pause.g and inform user via message box" according to the table here https://docs.duet3d.com/User_manual/RepRapFirmware/Events#processing-events

~~Create a file called 'driver-error.g' in /sys on the SD card. It could contain something like:~~

Create a file called 'driver-warning.g' in /sys on the SD card. It could contain something like:

M25 ; pause print
M0 ; cancel job (note cancel.g will be run)
M18 ; turn off motors
echo "Please check motor connection on driver "^{param.B}^"."^{param.D}

M0 may not be the behaviour you want, M1 or M112 might be more appropriate, or just pause. M18 will cause the motors to lose position, so will need rehoming if you want to continue with the job.

You can use M957 to simulate an event to check it works, see https://docs.duet3d.com/User_manual/RepRapFirmware/Events#simulating-events

To decrease the time it takes to pause a print, make sure that segmentation is enabled with M669.

Ian

gloomyandy

@droftarts phase disconnection is mentioned here:

Driver warning (e.g. over temperature warning, or phase disconnected, or closed loop driver position difference warning limit exceeded)

on this page: https://docs.duet3d.com/User_manual/RepRapFirmware/Events#events

So it would seem it is indeed a warning that will trigger driver-warning.g