6XD not moving the steppers unless I re-send M569 command

ComedianTF2

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ComedianTF2

After further testing, it seems that sending a small move command, after which sending the M569 command seems to enable them reliably.

At the bottom of the config.g I've added a M98 command calling for motor_enable.g, with the contents below

M98 P"motor_enable.g" ; enable motor at boot

M564 H0 S0					; allow unhomed moves + moves out of min/max area. Only for testing. Remove later on
G91 						; relative moves
G1 X0.1 					; move 0.1mmm
G1 Y0.1 					; move 0.1mmm
G1 Z0.1						; move 0.1mmm
M569 P0 S0 R1 T2:2:5:2.5	; X axis, Drive 0, active high enable, 2us minimum step pulse, 2 us minimum step interval, 5us DIR setup time and 5us hold time
M569 P1 S0 R1 T2:2:5:2.5	; Y axis
M569 P2 S0 R1 T2:2:5:2.5	; Z axis
M564 H1 S1 				; re-enable safety stuff

T3P3Tony

@ComedianTF2 which version of firmware are you running?

I am not sure if this is something strange about how those motors behave or an issue with firmware.

ComedianTF2

@T3P3Tony it's on 3.5.4

T3P3Tony

@ComedianTF2 do you have access to a scope or logic analyser? It would be good to understand if the enable and step lines are behaving as expected after the first M569, i.e it's an issue with those drivers, or not

droftarts

@ComedianTF2 The M569 command shouldn't enable the drivers, only configure them. Only sending M17, or sending a motor move, should enable the driver. You should be able to send M569 commands as often as you like after running config.g, and the driver should not enable. At least, that's what happens on the Mini 5+ I have here. Unfortunately I don't have a 6XD to test. You can send M569 P0 to check how the each driver output on the 6XD is configured.

How have you wired the stepper driver? I assume you have wired the EN+ from the driver to +5V on the 6XD, and EN- to D0 EN- on the 6XD, as shown here https://docs.duet3d.com/Duet3D_hardware/Duet_3_family/Duet_3_Mainboard_6XD_Hardware_Overview#connecting-external-motor-drivers. How is the 'Driver Enable Polarity' (En_Pol) jumper set?

In the table, it says

Drive initial time 2 - - s

The 'Drive initial time' of 2 seconds might be the reason that enable appears to be delayed. Try sending M17, wait 2 seconds, then a move. The manual also says:

The 4-28V signal level is used for protection of pulse, direction and enable.

It's possible that it's not reliably picking up the enable signal, which is 5V from the 6XD. Check your wiring. If you disconnect the enable wires, the driver should be enable at power on, and be enabled the whole time, which might be easier.

Ian

ComedianTF2

@T3P3Tony

I will be able to check that in January, once I'm back from holidays

@droftarts

Same, will test it out in January once I'm back. The wiring I've done per the guide you've shown. I had missed the driver enable polarity jumper, so that's quite likely the issue there.

With re-sending the commands we were able to get the printer up and running, and the printer has completed a successful print, though hopefully we won't need to use the driver_enable.g file I used before with the fixes recommended.

Thanks both for the help, I'll enjoy the Christmas break for now and get back to it in Jan

T3P3Tony

@ComedianTF2 do you have an update on this?

ComedianTF2

@T3P3Tony @droftarts

The 'Driver Enable Polarity' (En_Pol) jumper was on the left position, set to GND

Flipping the M569 R value from R1 to R0 fixed the issue. I think that by re-sending the M569 values, it basically sent the drive enable command to 0, which then allowed things to work.

Thanks for the support, I read the post and thought I had tested the R value inversion, but for some reason I must have done that testing incorrectly before, which caused me to not look at it properly until now.

T3P3Tony

@ComedianTF2 glad you have resolved it.