3.1.1 - BLtouch doesn't function after cancelling a job.

[Phaedrux]

Please post your config.g, your homing files, and your slicer start and end gcode. Also send a M122 and post the result.

Does the Bltouch work normally otherwise? You're able to home multiple times in a row?

[icecube45]

The BLTouch works as expected up until cancelling an active job. I'm able to run delta calibration, mesh bed probing, z=0 datum probing, manually send all the supported servo commands.

; Configuration file for Duet WiFi (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v2.1.8 on Thu May 21 2020 21:52:23 GMT-0700 (Pacific Daylight Time)
 
; General preferences
G90                                           ; send absolute coordinates...
M83                                           ; ...but relative extruder moves
M550 P"Bert"                                  ; set printer name
M665 R270 L476 B230 H885                      ; Set delta radius, diagonal rod length, printable radius and homed height
M666 X0 Y0 Z0                                 ; put your endstop adjustments here, or let auto calibration find them
 
; Network
M551 P"REDACTED"                                 ; set password
M552 S1                                       ; enable network
M586 P0 S1                                    ; enable HTTP
M586 P1 S0                                    ; disable FTP
M586 P2 S0                                    ; disable Telnet
 
; Drives
M569 P0 S0                                    ; physical drive 0 goes forwards
M569 P1 S0                                    ; physical drive 1 goes forwards
M569 P2 S0                                    ; physical drive 2 goes forwards
M569 P3 S0                                    ; physical drive 3 goes forwards
M584 X0 Y1 Z2 E3                              ; set drive mapping
M350 X16 Y16 Z16 E16 I1                       ; configure microstepping with interpolation
M92 X100.00 Y100.00 Z100.00 E2580.00          ; set steps per mm
M566 X1200.00 Y1200.00 Z1000.00 E1200.00      ; set maximum instantaneous speed changes (mm/min)
M203 X18000.00 Y18000.00 Z18000.00 E1200.00   ; set maximum speeds (mm/min)
M201 X1000.00 Y1000.00 Z1000.00 E1000.00      ; set accelerations (mm/s^2)
M906 X800 Y800 Z800 E800 I30               ; set motor currents (mA) and motor idle factor in per cent
M84 S30                                       ; Set idle timeout
 
; Axis Limits
M208 Z-2 S1                                    ; set minimum Z
 
; Endstops
M574 X2 S1 P"!xstop"                           ; configure active-low endstop for high end on X via pin xstop
M574 Y2 S1 P"!ystop"                           ; configure active-low endstop for high end on Y via pin ystop
M574 Z2 S1 P"!zstop"                           ; configure active-low endstop for high end on Z via pin zstop
 
; Z-Probe
M950 S0 C"exp.heater3"                        ; create servo pin 0 for BLTouch
M558 P9 C"zprobe.in+zprobe.mod" H5 F120 T12000 A10 S0.018
                                              ; set Z probe type to bltouch and the dive height + speeds
G31 P25 X24.54 Y-14.17 Z2.62                  ; set Z probe trigger value, offset and trigger height
M557 R160 S30                                 ; define mesh grid
 
; Heaters
M140 H-1                                      ; disable heated bed (overrides default heater mapping)
M308 S0 P"e0temp" Y"thermistor" T100000 B3974 ; configure sensor 0 as thermistor on pin e0temp
M950 H0 C"e0heat" T0                          ; create nozzle heater output on e0heat and map it to sensor 0
M143 H0 S280                                  ; set temperature limit for heater 0 to 280C
M307 H0 B0 S1.00                              ; disable bang-bang mode for heater  and set PWM limit
 
; Fans
M950 F0 C"fan0" Q500                          ; create fan 0 on pin fan0 and set its frequency
M106 P0 S0 H-1                                ; set fan 0 value. Thermostatic control is turned off
 
; LED Ring as Fan
M950 F1 C"fan1" Q500                          ; create fan 1 on pin fan1 and set its frequency
M106 P1 S0 H-1                                ; set fan 1 value. Thermostatic control is turned off
 
; Tools
M563 P0 D0 H0 F0                              ; define tool 0
G10 P0 X0 Y0 Z0                               ; set tool 0 axis offsets
G10 P0 R0 S0                                  ; set initial tool 0 active and standby temperatures to 0C
 
; Custom settings are not defined
M501
 
 

; homedelta.g
; called to home all towers on a delta printer
;
; generated by RepRapFirmware Configuration Tool v2.1.8 on Thu May 21 2020 21:52:24 GMT-0700 (Pacific Daylight Time)
G91                           ; relative positioning
G1 H1 X1005 Y1005 Z1005 F5000 ; move all towers to the high end stopping at the endstops (first pass)
G1 H2 X-5 Y-5 Z-5 F1800       ; go down a few mm
G1 H1 X10 Y10 Z10 F360        ; move all towers up once more (second pass)
G1 Z-5 F6000                  ; move down a few mm so that the nozzle can be centred
G90                           ; absolute positioning
G1 X0 Y0 F6000                ; move X+Y to the centre
 

start gcode

G90
M82
M106 S255
G28 ; home all axes
M104 S183 T0 ; set extruder temp
M109 S183 T0 ; wait for extruder temp
G1 Z10 F4000;
G1 X-24.54 Y14.17;
G30;
G29 S1;

end gcode

M104 S0 ; turn off extruder
M140 S0 ; turn off bed
G28;
M84 ; disable motors

[Phaedrux]

Do you have a cancel.g file in /sys?

[Phaedrux]

@icecube45 said in 3.1.1 - BLtouch doesn't function after cancelling a job.:

M558 P9 C"zprobe.in+zprobe.mod" H5 F120 T12000 A10 S0.018

Not sure if this will help, but modify this command to be:

M558 P9 C"^zprobe.in" H5 F120 T12000 A10 S0.018 R0.5

[icecube45]

@Phaedrux said in 3.1.1 - BLtouch doesn't function after cancelling a job.:

Not sure if this will help, but modify this command to be:
M558 P9 C"^zprobe.in" H5 F120 T12000 A10 S0.018 R0.5

I don't think recovery time would help, being as mesh probing/repeated probing works correctly.
I will try it when I get some free time anyhow.

If it helps, here are oscope traces from before and after cancelling a print, and sending the "pin down" command.
First trace results in pin down, second does not.
Looks like possible noise being introduced after a cancelled job? really unsure.
I should note that I don't remember this behavior occurring before updating to RRF 3.

[Phaedrux]

The main thing was removing the probe mod pin and adding the pullup resistor enable, but recovery/settle time is a good idea for the bltouch anyway.

Do you have a cancel.g in /sys?

Are the motors being disabled or going idle?

[icecube45]

@Phaedrux Oh sorry, I thought I had said. No I don't have a cancel.g

The bltouch doesn't work with motors idle or active when in this state - I discovered this after starting a new print and having my hotend crash into my build plate.

Will check the mod pin thing when I have a chance. Though I should note that's what the config tool spat out to me when I selected a bltouch.

[Phaedrux]

Yes the config tool has the mod pin selected by default. It's on the list to change. Only analogue probes that require modulation use it.

Can you try creating a cancel.g file? Either blank or with some sort of commands on what to do after cancelling.

Here's mine as example

; cancel.g
;
; Run when the print is paused, and then canceled.
;
 
G10 P0 R0 S0		; Set hotend temp to 0
M140 S0			; Set bed temp to 0
M106 S255 		; Fan at 100 to cool nozzle and bed
M220 S100		; Set speed factor back to 100% in case it was changed
M221 S100		; Set extrusion factor back to 100% in case it was changed
M290 R0 S0 ; clear babystepping
M204 P1000 T4000	; Set printing and travel accelerations
M566 X900 Y900 Z30 	; Set maximum instantaneous speed changes (mm/min) (Jerk)
G28 XY			; home XY
M98 P"0:/sys/CurrentsNormal.g" ; return motor currents to normal
M98 P"0:/sys/ZSpeedsNormal.g" ; return Z axis speeds to normal
M84			; turn off steppers
G4 S60			; wait 1 minute for nozzle to cool
M107			; turn off the fan
M98 P"0:/macros/Musical Tunes/TwoBits.g" ; play a tune

[icecube45]

A blank cancel.g and the M558 adjustments result in no change.

[Phaedrux]

What version of BLtouch is it by the way?

[icecube45]

@Phaedrux A 3.1, genuine.

[dc42]

Looks like you have a lot of stepper motor noise in your system. How have you connected the BLTouch to the Duet WiFi, in particular the two ground wires?

[icecube45]

Both ground wires are connected as described by the z-probe setup guide

But your comment on stepper noise had me thinking:
"If it's stepper noise, why does it only occur after cancelling a print, and not when I'm swinging the effector around beforehand"

Which led me to the root cause of my issue, my extruder stepper. Specifically (I guess), the hold current.

I tested this with manual control. BlTouch pin down, up. Works great.

Extrude 1mm, command BLTouch, no result.

Issue a M18 E0, bltouch immediately follows the last command sent.

So looks like my extruder stepper is the noisy one. This makes sense, following wire routing.

For now I guess I'll just issue a M18 within my cancel.g.

Unsure what would have caused this to only act up starting with RRF 3.1.1 - perhaps the configurator has a higher default extruder current than it did the last time I ran it?

[kodzianin]

@icecube45 Wow, i recently had this problem after switching from duet 2 to duet 3 mini 5+ and M18 E0 before homing worked like a charm, i think this problem might come from different TMC drivers and their switching frequency.

Thank you for sharing this solution.