@jay_s_uk awesome, I guess I'll pull the plug and go for it. Thanks!

Hey @jay_s_uk when you say "you can't at the moment" do you mean you can't at the moment because of a bug? Or do you mean you can't update to an -rc release in SBC in general? I ask because there does seem to be a version 3.5.3-rc1 in the repo here so I'm not really sure what the issue is. Could you help me understand?

Hey @droftarts, thanks for the heads up, and @dc42, enjoy your holiday! I just wanted to take a moment to express how impressed I am with the incredible hardware and software you guys create. My experience with the Mini 5+, 1LC, and magnetic filament monitor has been fantastic! The documentation is top-notch, and the forum is always such a helpful and well-organized place to find support. I know it can be tough and disheartening when all you hear are problems, so I wanted to share my appreciation for all your hard work and dedication. It really shows!

Hey @droftarts and @dc42 - FYI this issue is fixed in the alpha firmware linked by Andy Everitt in the github issue for this bug: https://github.com/Duet3D/RepRapFirmware/issues/1039 Thanks again for all your help on this!

droftarts created this issue in Duet3D/RepRapFirmware

closed [Bug]: Motor brake reports error when configured on mainboard used as expansion board #1039

@droftarts Ok, thanks! I'll repeat here what I posted on github, because I think it's important: I really don't want to come across as overly demanding - I fully appreciate how challenging it is to allocate resources in an open-source project. That said, the safety implicating of this particular issue are significant. I do have brakes on my z-stage motors but brakes clearly don't help in this situation. Although I guess you could argue a belted z-stage is a terrible idea in the first place anyway, again, I deeply respect the effort it takes to maintain an open-source project, so please don't take this as an entitled complaint - just a genuine concern I felt was worth sharing.

All that siad, I’m more than happy to take a more active role in debugging this issue, whether it involves hardware (I have multimeters, oscilloscopes, etc.) or software troubleshooting.

Hey @droftarts - just noticed this issue has been closed in github. Was this by mistake? Or has there been some resolution I'm not aware of?

@droftarts said in Motor current idle factor not working over canbus?:

Sorry, senior moment,

LOL, no worries, I know the feeling!

Could you test without stallguard and with the drivers in spreadCycle?

Just tried it, unfortunately no luck, problem still persists.

Otherwise I'll try and test early next week

Thank you! And please do let me know if there is anything I can do on my end to help with the debugging.

Hey @droftarts, I shared the configurations for both boards just a few days ago - you can find them here

I need to include the M906 I90 command in the config.g file for the expansion board; otherwise, the motors default to the default idle current, which causes my print plate to drop. For testing purposes, I remove that line. So, when I say the issue persists, I mean the problem still occurs when the M906 command is omitted from the expansion board’s config.g file. This was a workaround recommended by @dc42 himself here. Sorry, I know this is all a bit confusing, happy to jump on a quick voice call, to explain everything, if you think it could help?

EDIT: fixed links

Hey @droftarts, I hope this doesn’t make me sound crazy (though I wouldn’t blame you if it does!), but I just tested it in standalone mode, and the problem is still happening. I was sitting right next to the printer, with my hand under the print plate ready to catch it as soon as the low idle motor kicked in ... thankfully, I managed to catch it in time. I repeated the test several times with the same result. Anyway, I really don’t know what to do next. At this point I'm wondering if it's a hardware issue?

@kevinallen1902200 I'm planning to build a PrintNC router this winter and power it using duet closed-loop steppers. You might be interested in joining the printnc discord, I know a few people there that are discussing milling machines

@droftarts yup, running in SBC mode. Is our current running hypothesis that this could be an SBC-related issue? If so, would you like me to test without SBC mode on my end?

Hey @droftarts, sorry about for the late reply, the new house and the move and still taking up all my time. Anyway, yeah, I'm still experiencing the same problem. Here is a of my firmware, all 3.5.3. My setup is two Mini 5+ boards and SBC mode. Here is my config.g on the expansion board:

M906 I90
M954 A40

The issue happens whenever I remove the M906 command from the expansion board config. Below is my config.g for the main board. I'm very much new to duet so please do let me know if I'm doing anything dumb:

; get variables
M98 P"/sys/constants.g"

; General
G90  ; absolute coordinates
M83  ; relative extruder moves

; Wait a moment for the CAN expansion boards to become available
G4 S2

; Kinematics; Cartesian
M669 K0

; Drivers
M569 P0.0 S1 D3 V9   ; x0
M915 P0.0 S10        ; x0, stallguard threshold

M569 P0.1 S0 D3 V9   ; x1
M915 P0.1 S10        ; x1, stallguard threshold

M569 P0.2 S0 D3 V9   ; y0
M915 P0.2 S10        ; y0, stallguard threshold

M569 P0.3 S1 D3 V9   ; y1
M915 P0.3 S10        ; y1, stallguard threshold

M569 P40.0 S1 D3 V9  ; z0
M569 P40.1 S1 D3 V9  ; z1
M569 P40.2 S1 D3 V9  ; z2
M569 P40.3 S1 D3 V9  ; z3

M569 P121.0 S1 D3 V2   ; e

; ---- axes
M584 X0.0:0.1 Y0.2:0.3   Z40.0:40.1:40.2:40.3  E121.0      ; axis mapping

M350 X16      Y16        Z16      E16  I1     ; microstepping with interpolation
M906 X1200    Y1200      Z1200    E500        ; axis driver currents
M917 X100      Y100      Z100     E70         ; set motor standstill
M92  X79.87    Y79.80    Z160.31  E722.76     ; steps per mm
M208 X-10:270  Y-15:270  Z0:295               ; minimum and maximum axis limits

; ---- motor idle
M84  S600  ; idle timeout, 10min
M906 I95   ; idle current, 95%

; ---- accelerations and jerks
M203 X15000   Y15000   Z6000 E2000    ; maximum speeds (mm/min) E max: 8.3mm/sec, 20mm^3/sec
M201 X6000    Y6000    Z1000 E1000    ; accelerations  (mm/s^2) individual axes
M204 P6000 T3000                      ; accelerations  (mm/s^2) total motion, (P)rinting and (T)ravel
M566 X1200    Y1200    Z200  E400  P1 ; maximum instantaneous speed changes (mm/min)

; ---- temp Sensors
M308 S0 P"0.temp0"   Y"thermistor" A"Heated Bed"     T10000 B3892 ; bed
M308 S1 P"121.temp0" Y"pt1000"     A"Nozzle"                      ; nozzle
M308 S2 P"40.temp0"  Y"thermistor" A"Filament Dryer" T10000 B3892 ; filament dryer

; Fans
; --- air pump; brushed DC motors should operate nicely with a PWM freq of 50 to 100
M950 F0 C"0.out2" Q250
M106 P0 C"Tool fan"      S0 B0.0 H-1 L0 X0.5

; --- turn on auto when heatbreak is 45C
M950 F1 C"121.out2"
M106 P1 C"heatbreak fan" S0 B0.1 H1 T45 L0 X1

; --- BAG enclosure fan 1
M950 F3 C"!0.out3"
M106 P3 C"BAG fan 1 (weak)" S0 B0.1 H-1 L0 X1

M950 F4 C"!0.out4"
M106 P4 C"BAG fan 2 (strong)" S0 B0.1 H-1 L0 X1

; Heater, bed
M950 H0 C"0.out5" T0 Q500                          ; create heater #0
M140 P0 H0                                         ; configure heated bed #0
M143 H0 P0 T0 C0 S140 A0                           ; heater monitor #0 for heater #0
M307 H0 R0.645 K0.227:0.000 D11.51 E1.35 S1.00 B0  ; PID tune

; Heater, extruder
M950 H1 C"121.out0" T1   ; create heater #1
M143 H1 P1 T1 C0 S310 A0 ; configure heater monitor #0 for heater #1
M570 H1 P15 T20          ; fault only after 15sec and 20C excursion

if global.hotend == "magnum"
  M307 H1 R2.510 K0.449:0.000 D5.91 E1.35 S1.00 B0 V23.7
elif global.hotend == "mosquito"
  M307 H1 R3.039 K0.404:0.000 D5.22 E1.35 S1.00 B0 V23.4
else
  M307 H1 B1

; Endstops
M574 X1 S4
M574 Y1 S4
M574 Z0

; Tools
M563 P0 S"T0" D0 H1 F0 ; create tool #0
M568 P0 R0 S0          ; initial tool #0 active and standby temperatures to 0C
if global.nozzle_diameter < 0.6 ; heater feedforward for tool 0
  M309 P0 S0.08
if global.nozzle_diameter >= 0.6
  M309 P0 S0.3

; z-probe dock
M950 S0 C"out6" Q50    ; servo, assign GPIO port 1 to out9 (Servo header), servo mode
M950 J0 C"!0.io0.in"   ; sensor

; z brake
M569.7 P40.3 C"out1" S100

; accelerometer; I is the orientation
M955 P121.0 I24

; sensorless homing
M915 X Y R0 F0

; extra sensors
M308 S10 Y"mcu-temp" P"0.dummy"  A"0.MCU"
M308 S11 Y"mcu-temp" P"40.dummy" A"40.MCU"
M308 S12 Y"mcu-temp" P"121.dummy" A"121.MCU"

; electronics bag fan
M950 F5 C"40.out6"
M106 P5 C"electronics fan" B0.1 H11 T45 L0 X0.7

Finally, I know I did mention uploading a video, and I still can, if you think it would be helpful. However, it really wouldn't be too exciting, you'd just see the printer start up, and in the case when the expansion board config file lacks the line M906 I90 the z stage would drop... I have the cracks in some plastic parts at the bottom of the printer to prove it Anyway, let me know if there is anything else I can do to help!

@droftarts ok, sounds good, I'll try to get this for you this weekend. And to answer you question: I am running 4 motors on the z-axis

Hey @dc42, I just realized I left you hanging! Back on Sept 12, I replied with "Let me get back to you this weekend," but I got caught up in moving to a new house and haven't had much time to follow up. Sorry about that!