3.3b1CAN timeout resets itself?

[TypQxQ]

@dc42 I can’t remember the reason of last reset in that case.

I use separate PSU for the 6HC and 3HC. I use 32V on 6HC and 24V on 3HC. Short and thick cables but still diffrent PSUs.
The heated bed is on SSR.

This is my config:

; Configuration file for Duet 3 (firmware version 3)

; Maximum speed for e3d HighTorq at 31V, 1400mA (83% of 1680mA). (At 1500 back EMF is 32.7V so a no go.)
; Approximate peak back EMF due to rotation per motor: 14.1 V at 350.0 mm/s
; Approximate peak back EMF due to inductance per motor: 30.5 V at 350.0 mm/s
; Step pulse frequency: 56.0 kHz at 350.0 mm/s of max 300kHz with one stepper.
; Speed at which torque starts to drop (low slip angle): 241.2 mm/s @ 54.6 kHz
; Speed at which torque starts to drop (high slip angle): 315.8 mm/s @ 71.4 kHz



; ---------- General Preferences ----------
G90                                             ; send absolute coordinates...
M83                                             ; ...but relative extruder moves
M550 P"qTC"                                  	; set printer name
M929 P"eventlog.txt" S3							; start logging to file eventlog.txt Debug level
M669 K1                                         ; select CoreXY mode

; ---------- Drives ----------
;M569 P0.0 S0 F4                                 ; physical drive 0.0 goes forwards  X
;M569 P0.1 S1 F4                                 ; physical drive 0.1 goes forwards  Y
;M569 P0.0 S0	                                 ; physical drive 0.0 goes forwards  X
;M569 P0.1 S1	                                 ; physical drive 0.1 goes forwards  Y
M569 P0.2 S1	                                ; physical drive 0.2 goes forwards  Toolchanger Actuator
M569 P0.3 S1                                    ; physical drive 0.3 goes forwards	Z Back
M569 P0.4 S1                                    ; physical drive 0.4 goes forwards	Z Left
M569 P0.5 S1                                    ; physical drive 0.5 goes forwards	Z Front
;M569 P1.0 S1                                    ; physical drive 0.3 goes forwards	E0

M569 P0.0 S1	                                 ; physical drive 0.0 goes forwards  X
M569 P0.1 S0	                                 ; physical drive 0.1 goes forwards  Y
M569 P1.0 S1                                    ; physical drive 1.0 Y2
M569 P1.1 S0                                    ; physical drive 1.1 X2


;M569 P1.1 S1                                    ; physical drive 0.4 goes backwards E1
M569 P1.2 S1                                    ; physical drive 0.5 goes forwards	E2
;M584 X0.0 Y0.1 Z0.4:0.3:0.5 E1.0:1.1:1.2 U0.2 	; set drive mapping ( Z in the order of bed leveling )

;584 X1.1 Y1.0 Z0.4:0.3:0.5 E1.2 U0.2 	; set drive mapping ( Z in the order of bed leveling )
;M584 X0.1 Y0.0 Z0.4:0.3:0.5 E1.2 U0.2 	; set drive mapping ( Z in the order of bed leveling )
M584 X0.1:1.1 Y0.0:1.0 Z0.4:0.3:0.5 E1.2 U0.2 	; set drive mapping ( Z in the order of bed leveling )

M350 X16 Y16 I1
;M350 X32 Y32 I1
M350 E16 I1                    			; configure 16x for XY and E microstepping with interpolation
;M350 U4 I1                    					; configure 4x microstepping with interpolation for U, better torque
M350 U1 I1                    					; configure 1x microstepping with interpolation for U, better torque
M350 Z16 I1                    					; configure microstepping with interpolation. Full steps on Z means 200 steps per mm and a resolution of 0,005mm per step.
;M350 Z1 I1                    					; configure microstepping with interpolation. Full steps on Z means 200 steps per mm and a resolution of 0,005mm per step.

; ---------- Motor currents ----------
;M906 X2263 Y2263                        ; LDO XY motor currents (mA). 2263mA is 80% of 2828mA Peak Current. (2828mA Peak is 2000mA RMS)
                                        ; Do not exceed 90% of full XY motor current rating without heatsinking the XY motor drivers.
;M906 X1400 Y1400 								
;M906 X1400 Y1400 								

M906 X2000 Y1400 								

;M906 X1100 Y1100 								; set motor currents (mA) 1200 is Good up to 400mm/s without back EMF at 31,1V on one stepper
M906 Z1000 
M906 E900 										; 900 for BMG up to 135*C. Rated for 1.4A so runing at 86% with 1200
M906 U900 I60                           		; StepperOnline Toolchanger Elastic Lock Motor current and idle motor percentage, must be 60% idle and 90% current. Goes up to 120% when locking
M84 S30                                         ; Set idle timeout

; ---------- Steps per mm ----------
M92 X160 Y160 Z3200.00 E830 S16 		; set steps per mm as defined for 16 microsteps
M92 U11.515 S4                           			; Stepper-Online Toolchanger Elastic Lock Motor Steps/deg for U from (200 * 4 * 5.18181)/360

; ---------- Motor speeds ----------
M203 Z720 E3600 U9000 							; set maximum speeds (mm/min) (Z:12; E:60)
M566 Z100 E1200 U50     							; set maximum instantaneous speed changes (mm/min)
M201 Z100 E3000 U800     						; set accelerations (mm/s^2)

;M203 X18000 Y18000 							; set maximum speeds (mm/min) (XY:300) as maximum without slippage acording to EMF calculator.
M203 X33900 Y33900 								; set maximum speeds (mm/min) (XY:565) 70,8% of this is 400. Only one stepper wworking with max 400mm/s in diagonal

M201 X6000 Y6000		 						; set accelerations (mm/s^2) Tested upp till 9000  (e3d ToolChanger har 6000)
M566 X800 Y800 P1 								; set maximum instantaneous speed changes (mm/min) (5mm/s) Tested upp till 2500  (e3d ToolChanger har 400)
M204 P1000 T3000								; Print and Travel accelleration (e3d ToolChanger har ingen så 6000)


; ---------- Set axis software limits and min/max switch-triggering positions ----------
; ---------- Adjusted such that (0,0) lies at the lower left corner  ----------
M208 X-3:500 Y-6:515 Z-0.2:600					; Set the Xmin
M208 U0:200										; Set Elastic Lock (U axis) max rotation angle

; ---------- Kinematic bed ball locations ----------
M671 X-49.5:523.5:523.5 Y262.5:553:-37 S10
M557 X10:470 Y10:480 P10                        ; define mesh grid with 10 points in each direction

M98 P"/sys/custom/conf_EndStops.g"				; Configure EndStops and Emergency Stops.

; ---------- Bed Heater ----------
M308 S0 P"0.temp0" Y"thermistor" T10000 B3435 A"Bed"	; configure sensor 0 as thermistor on pin 1.temp0 for the thermistor on buildplate
M950 H0 C"0.out0" T0 Q1                        ; create bed heater output on 1.out0 and map it to sensor 0, PWM 10Hz (Default 500)

M308 S10 P"0.temp1" Y"thermistor" T100000 B4138 A"Bed Heater" ; configure sensor 20 as thermistor on pin 1.temp1 for the builtin thermistor

M143 H0 P0 T0 A0 S120                                 ; set temperature limit for bed 0 to 120C
M143 H0 P1 T10 A2 S120                                 ; set temperature limit for heater mat 0 to 120C but only switch off temporarily.
M143 H0 P2 T10 A0 S130                                 ; set temperature limit for heater mat 0 to 130C and generate heater error.

M307 H0 B0 S1.00                                ; disable bang-bang mode for the bed heater and set PWM limit
M140 H0                                         ; map heated bed to heater 0

M308 S11 P"0.temp2" Y"thermistor" T100000 B4138 A"X-Stepper" ; configure sensor 11 as thermistor on pin 0.temp2 for the builtin thermistor
M950 F11 C"0.out7"	                            ; Define X-Stepper Fan on out7 (2pin)
M950 F12 C"0.out8"	                            ; Define Y-Stepper Fan on out7 (2pin)
M106 P11 S255 T30 H11 C"X-Stepper Fan"          ; Setup Hotend Fan for thermal control, full on when XY-Stepper reaches 45C
M106 P12 S255 T30 H11 C"Y-Stepper Fan"          ; Setup Hotend Fan for thermal control, full on when XY-Stepper reaches 45C


; ---------- Tool definitions ----------
M98 P"/sys/custom/tool_0.g"						; Macro to load the tool definitions for Tool0
;M98 P"/sys/custom/tool_1.g"						; Macro to load the tool definitions for Tool1
;M98 P"/sys/custom/tool_2.g"						; Macro to load the tool definitions for Tool2
M563 P49 S"Z-Probe"								; Set up Tool49 as Z-Probe

; Miscellaneous
M501                                            ; load saved parameters from non-volatile memory

; ---------- Init heaters ----------
G10 P0 S0 R0			; Set tool 0 operating and standby temperatures(-273 = "off")
;G10 P1 S0 R0			; Set tool 1 operating and standby temperatures(-273 = "off")
;G10 P2 S0 R0			; Set tool 2 operating and standby temperatures(-273 = "off")
T0 P0
,T1 P0
;T2 P0
T-1 P0

It’s a CoreXY that I try running with 4 steppers, 2 on each belt, one in each corner:

[dc42]

Have you commoned and/or grounded the negative outputs of both power supplies, and if so, how?

Are the bed heater and SSR AC mains, or low voltage DC?

[TypQxQ]

@dc42 I haven’t commoned the negative and I don’t have ground in that room. I have an electrician booked for adding ground.
The ground cable is common to both PSUs, frame and the heated bed.
The SSR is on mains power.

[dc42]

Ok, you need to common the two negative PSU outputs.

[TypQxQ]

@dc42 That unfortunately didn't help.
I used a AWG18, 0.75mm cable of roughly 1,5m from one PSU tothe other, linking the negaive but it didn't help as seen below.
I have even tried 3 wires of 1,5mm mains cable now but it looks the same.

2021-03-01 20:16:39	m122 b1
Diagnostics for board 1:
Duet EXP3HC firmware version 3.3beta1 (2021-02-14 16:32:08)
Bootloader ID: SAME5x bootloader version 2.2 (2021-01-16b1)
Never used RAM 154840, free system stack 0 words
Tasks: Move(notifyWait,80) HEAT(delaying,69) CanAsync(notifyWait,72) CanRecv(notifyWait,82) CanClock(notifyWait,74) TMC(notifyWait,30) MAIN(running,209) AIN(delaying,260)
Last reset 01:27:20 ago, cause: software
Last software reset at 2020-11-10 18:16, reason: StackOverflow, available RAM 154112, slot 0
Software reset code 0x0100 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x0000080e BFAR 0xe000ed38 SP 0x2002ffb4 Task � Freestk 4294967295 ok
Stack: 2000137c 200013b0 0002525d 00000000 0003e418 20001598 20003b28 00000000 00024885 200014b4 20003ab0 00000000 00f00000 e000ef34 c0000000 20003b30 000249c5 0002472c 61000000 ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff
Driver 0: position 14403, 160.0 steps/mm,  ok, reads 30787, writes 0 timeouts 0, SG min/max 0/1023, steps req 34367743 done 34368699
Driver 1: position -542147, 160.0 steps/mm,  ok, reads 30787, writes 0 timeouts 0, SG min/max 0/1023, steps req 37364552 done 37365507
Driver 2: position 6290531, 830.0 steps/mm,  ok, reads 30788, writes 0 timeouts 0, SG min/max 0/1023, steps req 6969845 done 6969967
Moves scheduled 240234, completed 240233, in progress 1, hiccups 0, step errors 0, maxPrep 162, maxOverdue 3, maxInc 1, mcErrs 0, gcmErrs 0
Peak sync jitter 10, peak Rx sync delay 197, resyncs 0, next step interrupt due in 30 ticks, enabled
VIN: 24.1V, V12: 12.1V
MCU temperature: min 39.8C, current 40.0C, max 40.4C
Ticks since heat task active 162, ADC conversions started 5240154, completed 5240154, timed out 0
Last sensors broadcast 0x00000002 found 1 167 ticks ago, loop time 0
CAN messages queued 41311, send timeouts 0, received 259558, lost 0, free buffers 36, min 36, error reg 0
dup 0, oos 10, bm 0, wbm 0
2021-03-01 20:16:37	m122 b0
=== Diagnostics ===
RepRapFirmware for Duet 3 MB6HC version 3.3beta1 running on Duet 3 MB6HC v0.6 or 1.0 (SBC mode)
Board ID: 08DJM-956L2-G43S4-6JKDD-3SJ6L-TB62G
Used output buffers: 1 of 40 (15 max)
=== RTOS ===
Static ram: 148196
Dynamic ram: 62844 of which 156 recycled
Never used RAM 139476, free system stack 118 words
Tasks: Linux(ready,121) HEAT(delaying,283) CanReceiv(notifyWait,799) CanSender(notifyWait,357) CanClock(delaying,349) TMC(notifyWait,18) MAIN(running,664) IDLE(ready,20)
Owned mutexes: HTTP(MAIN)
=== Platform ===
Last reset 01:27:18 ago, cause: software
Last software reset at 2021-03-01 18:49, reason: User, none spinning, available RAM 139968, slot 0
Software reset code 0x0012 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x00400000 BFAR 0x00000000 SP 0x00000000 Task Linu Freestk 0 n/a
Error status: 0x00
Aux0 errors 0,0,0
Aux1 errors 0,0,0
MCU temperature: min 43.2, current 44.3, max 44.5
Supply voltage: min 31.8, current 31.9, max 32.0, under voltage events: 0, over voltage events: 0, power good: yes
12V rail voltage: min 12.0, current 12.0, max 12.1, under voltage events: 0
Driver 0: position 72683, ok, reads 21418, writes 0 timeouts 0, SG min/max 0/1023
Driver 1: position -6130, ok, reads 21418, writes 0 timeouts 0, SG min/max 0/1023
Driver 2: position 22157, standstill, reads 21418, writes 0 timeouts 0, SG min/max not available
Driver 3: position 294, ok, reads 21419, writes 0 timeouts 0, SG min/max 0/1023
Driver 4: position 0, ok, reads 21419, writes 0 timeouts 0, SG min/max 0/1023
Driver 5: position 0, ok, reads 21418, writes 0 timeouts 0, SG min/max 0/1023
Date/time: 2021-03-01 20:16:36
Slowest loop: 47.84ms; fastest: 0.07ms
=== Storage ===
Free file entries: 10
SD card 0 not detected, interface speed: 37.5MBytes/sec
SD card longest read time 0.0ms, write time 0.0ms, max retries 0
=== Move ===
DMs created 125, maxWait 0ms, bed compensation in use: mesh, comp offset 0.000
=== MainDDARing ===
Scheduled moves 239745, completed moves 239685, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state 3
=== AuxDDARing ===
Scheduled moves 0, completed moves 0, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== Heat ===
Bed heaters = 0 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1, chamberHeaters = -1 -1 -1 -1
Heater 0 is on, I-accum = 0.1
Heater 1 is on, I-accum = 0.0
=== GCodes ===
Segments left: 1
Movement lock held by null
HTTP* is doing "M122 B0" in state(s) 0
Telnet is idle in state(s) 0
File* is doing "G1 X263.445007 Y236.496994 E0.009150" in state(s) 0
USB is idle in state(s) 0
Aux is idle in state(s) 0
Trigger* is idle in state(s) 0
Queue* is idle in state(s) 0
LCD is idle in state(s) 0
SBC is idle in state(s) 0
Daemon is idle in state(s) 0
Aux2 is idle in state(s) 0
Autopause is idle in state(s) 0
Code queue is empty.
=== CAN ===
Messages queued 261807, send timeouts 3080, received 41749, lost 0, longest wait 23ms for reply type 6024, peak Tx sync delay 523, free buffers 49 (min 33)
=== SBC interface ===
State: 4, failed transfers: 0
Last transfer: 1ms ago
RX/TX seq numbers: 64446/64446
SPI underruns 0, overruns 0
Number of disconnects: 0, IAP RAM available 0x2d3c4
Buffer RX/TX: 1056/2336-0
=== Duet Control Server ===
Duet Control Server v3.2.2
File:
Buffered code: G1 X263.255 Y236.223 E0.00932
Buffered code: G1 X262.925 Y235.845 E0.01406
Buffered code: G1 X262.556 Y235.505 E0.01406
Buffered code: G1 X262.152 Y235.208 E0.01406
Buffered code: G1 X261.717 Y234.957 E0.01406
Buffered code: G1 X261.257 Y234.755 E0.01406
Buffered code: G1 X260.778 Y234.605 E0.01406
Buffered code: G1 X260.286 Y234.509 E0.01406
Buffered code: G1 X259.786 Y234.468 E0.01406
Buffered code: G1 X259.284 Y234.482 E0.01406
Buffered code: G1 X258.787 Y234.550 E0.01406
Buffered code: G1 X258.300 Y234.674 E0.01406
Buffered code: G1 X257.830 Y234.850 E0.01406
Buffered code: G1 X257.382 Y235.076 E0.01406
Buffered code: G1 X256.962 Y235.351 E0.01406
Buffered code: G1 X256.574 Y235.670 E0.01406
Buffered code: G1 X256.224 Y236.030 E0.01406
Buffered code: G1 X255.916 Y236.426 E0.01406
Buffered code: G1 X255.653 Y236.853 E0.01406
Buffered code: G1 X255.439 Y237.307 E0.01406
Buffered code: G1 X255.276 Y237.782 E0.01406
Buffered code: G1 X255.166 Y238.272 E0.01406
Buffered code: G1 X255.111 Y238.771 E0.01406
Buffered code: G1 X255.111 Y239.273 E0.01406
Buffered code: G1 X255.166 Y239.772 E0.01406
Buffered code: G1 X255.276 Y240.261 E0.01406
Buffered code: G1 X255.439 Y240.736 E0.01406
Buffered code: G1 X255.653 Y241.190 E0.01406
Buffered code: G1 X255.916 Y241.618 E0.01406
Buffered code: G1 X256.224 Y242.014 E0.01406
Buffered code: G1 X256.574 Y242.374 E0.01406
==> 1488 bytes
Code buffer space: 1520
Configured SPI speed: 8000000 Hz
Full transfers per second: 56.09
Maximum length of RX/TX data transfers: 3824/1688
File /opt/dsf/sd/gcodes/RearLeft v6.2.gcode is selected, processing

[T3P3Tony]

@TypQxQ out of intrest did you get these issues with CAN send timeouts on RRF 3.2?

[TypQxQ]

@T3P3Tony I’m not sure. I didn’t have the extra XY motors on the 3HC back then. My logs show 2 timeouts at an instance on 3.2.2 but not more than that.

I left the printer on overnight just idling and that generated no timeouts which makes me wonder if it has something to do with amount of messages/s.

After idling for about 7h:

6HC:
Messages queued 212635, send timeouts 0, received 283521, lost 0, longest wait 0ms for reply type 0, peak Tx sync delay 514, free buffers 49 (min 49)
3HC:
CAN messages queued 436976, send timeouts 0, received 689661, lost 0, free buffers 36, min 36, error reg 0

While printing, before canceling and letting the printer idle:

6HC:
Messages queued 454219, send timeouts 6845, received 128018, lost 0, longest wait 1ms for reply type 6013, peak Tx sync delay 514, free buffers 49 (min 33)
3HC:
CAN messages queued 436976, send timeouts 0, received 689661, lost 0, free buffers 36, min 36, error reg 0
dup 0, oos 16, bm 8, wbm 9772795

[dc42]

@TypQxQ, please confirm that the config.g file that you posted on 28 Feb is the one you used during that print, and provide the GCode file you were printing during that test this morning. Then I will run it on my bench setup. The last part of the 3HC diagnostics "oos 16, bm 8, wbm 9772795" are a particular concern.

[TypQxQ]

@dc42 Should be that config but I attach it here again.
Also my eventlog and the gcode file.

https://we.tl/t-LXCxEDaMXP

I want to test without any motors connected when I get home later today. Plan to disconnect them and put them at 100mA not to get disconnection errors.

[dc42]

@TypQxQ said in 3.3b1CAN timeout resets itself?:

@dc42 Should be that config but I attach it here again.
Also my eventlog and the gcode file.

https://we.tl/t-LXCxEDaMXP

I want to test without any motors connected when I get home later today. Plan to disconnect them and put them at 100mA not to get disconnection errors.

Thanks, that's a good plan. I'll probably run it the same way.

[dc42]

@TypQxQ, please provide your sys/custom/tool_0.g and sys/custom/conf_Endstops.g files.

[TypQxQ]

@dc42 said in 3.3b1CAN timeout resets itself?:

@TypQxQ, please provide your sys/custom/tool_0.g and sys/custom/conf_Endstops.g files.

Here is everything in my config and customconfig folder.
https://we.tl/t-xwMjBHKrGd

Thank you!

[dc42]

Thanks, I am running that job now. How long did you leave it running last time, before you ran M122 B1 and got this message?

CAN messages queued 436976, send timeouts 0, received 689661, lost 0, free buffers 36, min 36, error reg 0
dup 0, oos 16, bm 8, wbm 9772795

[dc42]

Progress update. Running your job and your configuration, I am seeing a lot of send timeouts (in the M122 report) on the MB6HC. The number of out-of-sequence messages received on the EXP3HC ('oos' in the M122 B1 report) is much lower, suggesting that most of the send timeouts are spurious; but the fact that they occur at all indicates a problem. I will keep you informed.

[dc42]

It appears that with a code change I have resolved the send timeouts and associated 'oos' reports. Your print has been running for 76 minutes now with no error reports.

I still haven't seen any of the 'bm' reports on my system. They are likely to have a different cause.

I forgot to ask one thing. As I understand it, your system has just a MB6HC and one EXP3HC connected via CAN, and no other CAN-connected boards. Have you fitted the CAN termination jumpers to the EXP3HC board?

PS - if you want to try the 6HC and 3HC firmware binaries that I am running, you can find them here https://www.dropbox.com/sh/q5uqqkjbmhgvlhq/AACYqG0ynLME9ogoLd1zLB2Xa?dl=0.

[TypQxQ]

@dc42 said in 3.3b1CAN timeout resets itself?:

It appears that with a code change I have resolved the send timeouts and associated 'oos' reports. Your print has been running for 76 minutes now with no error reports.

I still haven't seen any of the 'bm' reports on my system. They are likely to have a different cause.

I forgot to ask one thing. As I understand it, your system has just a MB6HC and one EXP3HC connected via CAN, and no other CAN-connected boards. Have you fitted the CAN termination jumpers to the EXP3HC board?

This is great news!
I can confirm my CAN termination jumpers are closed on 3HC.
I plan is to buy another 3HC if I get multiple motors on XY to work

@dc42 said in 3.3b1CAN timeout resets itself?:

Thanks, I am running that job now. How long did you leave it running last time, before you ran M122 B1 and got this message?

Not sure what if you mean time since reboot or since stopped printing.
According to the eventlog above, "Last reset 10:14:33 ago" and was idle for almost 8h.

When it was printing and had an uptime of 00:07:53 it read:

CAN messages queued 3305, send timeouts 222, received 2369, lost 0, free buffers 36, min 36, error reg 100000
dup 0, oos 0, bm 4, wbm 5559827

[dc42]

What I meant was, how long did you have to print for to get a nonzero 'bm' value when you ran M122 B1? Because I haven't seen any yet. Looks like 7 minutes may have been enough for you.

[TypQxQ]

@dc42 said in 3.3b1CAN timeout resets itself?:

What I meant was, how long did you have to print for to get a nonzero 'bm' value when you ran M122 B1? Because I haven't seen any yet. Looks like 7 minutes may have been enough for you.

Trying the new firmware right now.
I don't know what BM and WBM stands for but I got them again after 00:13:24 :

CAN messages queued 6740, send timeouts 0, received 6156, lost 0, free buffers 36, min 36, error reg 0
dup 0, oos 0, bm 12, wbm 15972458

Also before printing I had some error reg. at uptime of 00:03:24:

CAN messages queued 2083, send timeouts 0, received 1735, lost 0, free buffers 36, min 36, error reg 110000
dup 0, oos 0, bm 0, wbm 0

Now printing without any timeouts so far but only 20min inside print.

[dc42]

'bm' is the bad move command count, which I put in temporarily to debug a previous issue. That's the count of move commands that were scheduled to start before the previous move had ended. 'wbm' is a record of the worst bad instance; the figure is how many 750kHz clock ticks the new move was supposed to start before the previous move had finished. So your 'wbm' figure of 5559827 indicates that a move was scheduled to start 7.4 seconds before the previous move ended.

I don't see a nonzero bad move command count on my machine. However, it's occurred to me that you might legitimately have this situation after homing. I don't do homing of my simulation of your machine, I just use G92 to set all the axis positions. But if you are homing an axis connected to the EXP3HC, then that homing move might be scheduled to take e.g. 10 seconds but stop after 3 seconds when it triggers the homing switch. Then the next move will start before the homing move was originally scheduled to end, triggering the bad move command logging.

I will fix the bad move command counter to take account of moves that complete before they were originally scheduled to complete.

PS:

1. I've just replaced the EXP3HC binary at https://www.dropbox.com/sh/q5uqqkjbmhgvlhq/AACYqG0ynLME9ogoLd1zLB2Xa?dl=0 to include that change to the bad move count logging.
2. My print has been going for almost 5 hours now. During that time it has recorded just one send timeout on the main board while sending a movement message. I think it must be spurious, because there wasn't a corresponding 'oos' (out of sequence) error on the EXP3HC, which I would expect if the 3HC hadn't received the move.

[TypQxQ]

@dc42 I have finished printing and after 9h16m the print looks good and I also only received one timeout:

Messages queued 1750358, send timeouts 1, received 362388, lost 0, longest wait 24ms for reply type 6024, peak Tx sync delay 578, free buffers 49 (min 47)
CAN messages queued 361984, send timeouts 0, received 1747438, lost 0, free buffers 36, min 36, error reg 0
dup 0, oos 0, bm 0, wbm 0

I loaded the new 3HC firmware with time 22:51 on Dropbox and will run it again. But the time compile time in M122 hasn't changed after updating this morning: "Duet EXP3HC firmware version 3.3beta1+1 (2021-03-02 15:56:53)"

Thank You!!! It this looks sooo good!

2021-03-03 05:32:39 Finished printing file 0:/gcodes/RearLeft v6.2.gcode, print time was 9h 16m
2021-03-03 06:30:00 === Diagnostics ===
RepRapFirmware for Duet 3 MB6HC version 3.3beta1+1 running on Duet 3 MB6HC v0.6 or 1.0 (SBC mode)
Board ID: 08DJM-956L2-G43S4-6JKDD-3SJ6L-TB62G
Used output buffers: 1 of 40 (17 max)
=== RTOS ===
Static ram: 148212
Dynamic ram: 62952 of which 0 recycled
Never used RAM 143028, free system stack 98 words
Tasks: Linux(ready,63) HEAT(delaying,284) CanReceiv(notifyWait,774) CanSender(notifyWait,359) CanClock(delaying,342) TMC(notifyWait,18) MAIN(running,649) IDLE(ready,20)
Owned mutexes: HTTP(MAIN)
=== Platform ===
Last reset 10:23:58 ago, cause: power up
Last software reset at 2021-03-02 19:50, reason: User, none spinning, available RAM 139760, slot 2
Software reset code 0x0012 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x00400000 BFAR 0x00000000 SP 0x00000000 Task Linu Freestk 0 n/a
Error status: 0x00
Aux0 errors 0,0,0
Aux1 errors 0,0,0
MCU temperature: min 43.3, current 43.5, max 44.8
Supply voltage: min 31.8, current 31.9, max 32.0, under voltage events: 0, over voltage events: 0, power good: yes
12V rail voltage: min 12.0, current 12.1, max 12.1, under voltage events: 0
Driver 0: position 160000, standstill, reads 5226, writes 2 timeouts 0, SG min/max 0/1023
Driver 1: position 0, standstill, reads 5227, writes 2 timeouts 0, SG min/max 0/1023
Driver 2: position 311549, standstill, reads 5227, writes 2 timeouts 0, SG min/max 0/158
Driver 3: position 0, standstill, reads 5227, writes 2 timeouts 0, SG min/max 0/1023
Driver 4: position 0, standstill, reads 5227, writes 2 timeouts 0, SG min/max 0/1023
Driver 5: position 0, standstill, reads 5226, writes 2 timeouts 0, SG min/max 0/1023
Date/time: 2021-03-03 06:29:58
Slowest loop: 90.33ms; fastest: 0.05ms
=== Storage ===
Free file entries: 10
SD card 0 not detected, interface speed: 37.5MBytes/sec
SD card longest read time 0.0ms, write time 0.0ms, max retries 0
=== Move ===
DMs created 125, maxWait 286ms, bed compensation in use: mesh, comp offset 0.000
=== MainDDARing ===
Scheduled moves 1889328, completed moves 1889328, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== AuxDDARing ===
Scheduled moves 0, completed moves 0, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== Heat ===
Bed heaters = 0 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1, chamberHeaters = -1 -1 -1 -1
Heater 0 is on, I-accum = 0.1
=== GCodes ===
Segments left: 0
Movement lock held by null
HTTP* is doing "M122 B0" in state(s) 0
Telnet is idle in state(s) 0
File* is idle in state(s) 0
USB is idle in state(s) 0
Aux is idle in state(s) 0
Trigger* is idle in state(s) 0
Queue* is idle in state(s) 0
LCD is idle in state(s) 0
SBC is idle in state(s) 0
Daemon is idle in state(s) 0
Aux2 is idle in state(s) 0
Autopause is idle in state(s) 0
Code queue is empty.
=== CAN ===
Messages queued 1750358, send timeouts 1, received 362388, lost 0, longest wait 24ms for reply type 6024, peak Tx sync delay 578, free buffers 49 (min 47)
Last cancelled message type 51 dest 1
=== SBC interface ===
State: 4, failed transfers: 0
Last transfer: 1ms ago
RX/TX seq numbers: 40775/40775
SPI underruns 0, overruns 0
Number of disconnects: 0, IAP RAM available 0x2d3ac
Buffer RX/TX: 0/0-0
2021-03-03 06:30:03 Diagnostics for board 1:
Duet EXP3HC firmware version 3.3beta1+1 (2021-03-02 15:56:53)
Bootloader ID: SAME5x bootloader version 2.2 (2021-01-16b1)
Never used RAM 154884, free system stack 0 words
Tasks: Move(notifyWait,80) HEAT(delaying,69) CanAsync(notifyWait,72) CanRecv(notifyWait,82) CanClock(notifyWait,74) TMC(notifyWait,30) MAIN(running,301) AIN(delaying,260)
Last reset 10:24:02 ago, cause: power up
Last software reset at 2020-11-10 18:16, reason: StackOverflow, available RAM 154112, slot 0
Software reset code 0x0100 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x0000080e BFAR 0xe000ed38 SP 0x2002ffb4 Task � Freestk 4294967295 ok
Stack: 2000137c 200013b0 0002525d 00000000 0003e418 20001598 20003b28 00000000 00024885 200014b4 20003ab0 00000000 00f00000 e000ef34 c0000000 20003b30 000249c5 0002472c 61000000 ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff
Driver 0: position -1440, 160.0 steps/mm,  standstill, reads 17400, writes 2 timeouts 0, SG min/max 0/1023, steps req 268204856 done 268206165
Driver 1: position -144480, 160.0 steps/mm,  standstill, reads 17399, writes 2 timeouts 0, SG min/max 0/1023, steps req 271278668 done 271279392
Driver 2: position 48970973, 830.0 steps/mm,  standstill, reads 17397, writes 2 timeouts 0, SG min/max 0/1023, steps req 47753506 done 47753659
Moves scheduled 1888753, completed 1888753, in progress 0, hiccups 0, step errors 0, maxPrep 191, maxOverdue 5, maxInc 1, mcErrs 0, gcmErrs 0
Peak sync jitter 11, peak Rx sync delay 198, resyncs 30, no step interrupt scheduled
VIN: 24.1V, V12: 12.1V
MCU temperature: min 39.8C, current 40.0C, max 40.2C
Ticks since heat task active 64, ADC conversions started 37442556, completed 37442554, timed out 0
Last sensors broadcast 0x00000002 found 1 68 ticks ago, loop time 0
CAN messages queued 361984, send timeouts 0, received 1747438, lost 0, free buffers 36, min 36, error reg 0
dup 0, oos 0, bm 0, wbm 0
2021-03-03 06:55:17 G10 P0 S220

Before and after the timeout fix:

And final again:

2021-03-03 18:14:05	m122 b0
=== Diagnostics ===
RepRapFirmware for Duet 3 MB6HC version 3.3beta1+1 running on Duet 3 MB6HC v0.6 or 1.0 (SBC mode)
Board ID: 08DJM-956L2-G43S4-6JKDD-3SJ6L-TB62G
Used output buffers: 1 of 40 (21 max)
=== RTOS ===
Static ram: 148212
Dynamic ram: 62904 of which 0 recycled
Never used RAM 143076, free system stack 98 words
Tasks: Linux(ready,69) HEAT(delaying,284) CanReceiv(notifyWait,774) CanSender(notifyWait,359) CanClock(delaying,342) TMC(notifyWait,18) MAIN(running,649) IDLE(ready,20)
Owned mutexes: HTTP(MAIN)
=== Platform ===
Last reset 10:54:16 ago, cause: software
Last software reset at 2021-03-03 07:19, reason: User, none spinning, available RAM 143444, slot 2
Software reset code 0x0012 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x00400000 BFAR 0x00000000 SP 0x00000000 Task Linu Freestk 0 n/a
Error status: 0x00
Aux0 errors 0,0,0
Aux1 errors 0,0,0
MCU temperature: min 42.1, current 43.6, max 45.1
Supply voltage: min 31.8, current 31.9, max 32.0, under voltage events: 0, over voltage events: 0, power good: yes
12V rail voltage: min 12.0, current 12.0, max 12.1, under voltage events: 0
Driver 0: position 160000, standstill, reads 42231, writes 2 timeouts 0, SG min/max 0/1023
Driver 1: position 0, standstill, reads 42231, writes 2 timeouts 0, SG min/max 0/1023
Driver 2: position 311549, standstill, reads 42227, writes 6 timeouts 0, SG min/max 0/156
Driver 3: position 0, standstill, reads 42231, writes 2 timeouts 0, SG min/max 0/1023
Driver 4: position 0, standstill, reads 42231, writes 2 timeouts 0, SG min/max 0/1023
Driver 5: position 0, standstill, reads 42231, writes 2 timeouts 0, SG min/max 0/1023
Date/time: 2021-03-03 18:14:02
Slowest loop: 1001.41ms; fastest: 0.05ms
=== Storage ===
Free file entries: 10
SD card 0 not detected, interface speed: 37.5MBytes/sec
SD card longest read time 0.0ms, write time 0.0ms, max retries 0
=== Move ===
DMs created 125, maxWait 7881ms, bed compensation in use: mesh, comp offset 0.000
=== MainDDARing ===
Scheduled moves 1889328, completed moves 1889328, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 1, 0], CDDA state -1
=== AuxDDARing ===
Scheduled moves 0, completed moves 0, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== Heat ===
Bed heaters = 0 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1, chamberHeaters = -1 -1 -1 -1
Heater 0 is on, I-accum = 0.1
=== GCodes ===
Segments left: 0
Movement lock held by null
HTTP* is doing "M122 B0" in state(s) 0
Telnet is idle in state(s) 0
File* is idle in state(s) 0
USB is idle in state(s) 0
Aux is idle in state(s) 0
Trigger* is idle in state(s) 0
Queue* is idle in state(s) 0
LCD is idle in state(s) 0
SBC is idle in state(s) 0
Daemon is idle in state(s) 0
Aux2 is idle in state(s) 0
Autopause is idle in state(s) 0
Code queue is empty.
=== CAN ===
Messages queued 2236102, send timeouts 4, received 463095, lost 0, longest wait 20ms for reply type 6024, peak Tx sync delay 554, free buffers 49 (min 47)
Last cancelled message type 51 dest 1
=== SBC interface ===
State: 4, failed transfers: 0
Last transfer: 1ms ago
RX/TX seq numbers: 39306/39306
SPI underruns 0, overruns 0
Number of disconnects: 0, IAP RAM available 0x2d3dc
Buffer RX/TX: 0/0-0
=== Duet Control Server ===
Duet Control Server v3.2.2
Code buffer space: 4096
Configured SPI speed: 8000000 Hz
Full transfers per second: 51.37
Maximum length of RX/TX data transfers: 5092/1688
2021-03-03 18:13:58	m122 b1
Diagnostics for board 1:
Duet EXP3HC firmware version 3.3beta1+1 (2021-03-02 15:56:53)
Bootloader ID: SAME5x bootloader version 2.2 (2021-01-16b1)
Never used RAM 154884, free system stack 0 words
Tasks: Move(notifyWait,80) HEAT(delaying,69) CanAsync(notifyWait,72) CanRecv(notifyWait,82) CanClock(notifyWait,74) TMC(notifyWait,30) MAIN(running,331) AIN(delaying,260)
Last reset 10:54:27 ago, cause: software
Last software reset at 2020-11-10 18:16, reason: StackOverflow, available RAM 154112, slot 0
Software reset code 0x0100 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x0000080e BFAR 0xe000ed38 SP 0x2002ffb4 Task � Freestk 4294967295 ok
Stack: 2000137c 200013b0 0002525d 00000000 0003e418 20001598 20003b28 00000000 00024885 200014b4 20003ab0 00000000 00f00000 e000ef34 c0000000 20003b30 000249c5 0002472c 61000000 ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff
Driver 0: position -480, 160.0 steps/mm,  standstill, reads 62626, writes 2 timeouts 0, SG min/max 0/1023, steps req 333181004 done 333181004
Driver 1: position -48160, 160.0 steps/mm,  standstill, reads 62625, writes 2 timeouts 0, SG min/max 0/1023, steps req 340878416 done 340878416
Driver 2: position 48970973, 830.0 steps/mm,  standstill, reads 62625, writes 3 timeouts 0, SG min/max 0/1023, steps req 60334361 done 60334361
Moves scheduled 1888677, completed 1888677, in progress 0, hiccups 0, step errors 0, maxPrep 180, maxOverdue 4, maxInc 2, mcErrs 0, gcmErrs 0
Peak sync jitter 11, peak Rx sync delay 204, resyncs 36, no step interrupt scheduled
VIN: 24.1V, V12: 12.1V
MCU temperature: min 39.8C, current 40.0C, max 40.2C
Ticks since heat task active 155, ADC conversions started 39267896, completed 39267896, timed out 0
Last sensors broadcast 0x00000002 found 1 160 ticks ago, loop time 0
CAN messages queued 462985, send timeouts 0, received 2236041, lost 0, free buffers 36, min 36, error reg 0
dup 0, oos 0, bm 0, wbm 0
2021-03-03 16:46:53	Finished printing file 0:/gcodes/RearLeft v6.2.gcode, print time was 9h 18m