[RRF 2.02] M703 blocking or async?

[wilriker]

Duet Web Control 2.0.0-RC3 
 
Electronics: Duet WiFi 1.02 or later 
Firmware: RepRapFirmware for Duet 2 WiFi/Ethernet 2.02(RTOS) (2018-12-24b1) 
Duet WiFi Server Version: 1.22 

I changed my setup regarding what the slicer does and what is configured directly on the Duet yesterday and stumbled across something strange with the second print.

Setup

I have a start.g that looks like the following:

; start.g
; called by RRF when a print is started (not though when resumed)
M80          ; Turn the VIN PSU on
 
G21          ; metric values
G90          ; absolute positioning
M83          ; relative extrusion mode
M106 P0 S0   ; start with the fan off
M703         ; Load filament's config.g (includes heating)
M350 E128 I0 ; Increase ustep factor on extruder to x128
 
G28          ; home all axes

My filament's config.g loaded by the above M703 looks like this:

M207 S2.0 F6000 T2000 Z0.0    ; Firmware retract settings
M572 D0 S0.1                  ; Pressure Advance
 
M140 S70                      ; set bed temp
M116 H0                       ; wait for bed temp
G10 P0 S230                   ; set extruder temp
M116 P0                       ; wait for extruder temp

My slicer is configured to not issue any commands related to heating and nothing in its start codes section.

Expected Behavior

What I expect from these codes would be the following:

• when starting a print

1. heat the bed
2. heat the hotend
3. home all axes

• start printing
• at the end of a print I call M0 which in turn calls stop.g (I do not have a cancel.g anymore)

; stop.g
; called when M0 (Stop) is run (e.g. when a print from SD card is cancelled)
;
; generated by RepRapFirmware Configuration Tool on Sat Apr 28 2018 20:07:26 GMT+0200 (CEST)
G10 P0 R-273.15 S-273.15 ; extruder heater off
M140 S-273.15            ; bed heater off
 
[do some movements and turn off PSU]

Observed Behavior

Now, this worked for the first print as expected. The second print though the following order was observed:

1. home all axes
2. heat the bed
3. heat the hotend

I printed the exact same GCode again that worked the first time but the second time it did the homing first not last. In my case this is an issue because I have set M906 ... I0 and M84 S120 and heating takes longer than 120s so the motors had been turned off and at the start of the print the axes where no longer homed.

Speculated Reason

My guess is that it has to to with the commands in stop.g that turn the heaters off.

[dc42]

You are using unsupported old release candidate firmware, so please upgrade your firmware to 2.02.

I recall that there was a bug in older firmware that affected the last line of a macro file under some conditions, and that might responsible for what you observe.

A common reason for a second print not behaving the same way as the first print is to do with whether or not a tool is selected before you start the print.

[wilriker]

@dc42 You might have misread the listing of the versions. It is DWC that is running 2.0-RC3. RRF is 2.02 final.

EDIT:
I do have T0 in my config.g and also just one tool selected. I never deselect the tool - or is that done by G10 P0 R-273.15 S-273.15?

Also why would it skip bed heating in this case?

[dc42]

@wilriker said in [RRF 2.02] M703 blocking or async?:

@dc42 You might have misread the listing of the versions. It is DWC that is running 2.0-RC3. RRF is 2.02 final.

I'm sorry, I did indeed misread that.

Your G10 command should not deselect the tool, although M0 will if you don't have a stop.g file. You are right, even if no tool is selected, it should still wait for the bed to heat up.

[wilriker]

@dc42 I do have a stop.g (but not cancel.g) that does contain the above G10 command.

Now I added explicit T0 to the beginning of my start.g and it seems to fix the issue.

EDIT: the tool was listed as off in DWC after the print finished. T0 in start.g changes it to active.

EDIT2: As an aside on this:
G10 P P0 R-273.15 S-273.15 does turn the tool to off and sets both active and standby temperatures to 0°C
M140 S-273.15 does turn the bed heater to off but it leaves its active temperature (and probably also the standby temperature) at the last set value.

Is this difference intented?

[dc42]

@wilriker said in [RRF 2.02] M703 blocking or async?:

As an aside on this:
G10 P P0 R-273.15 S-273.15 does turn the tool to off and sets both active and standby temperatures to 0°C
M140 S-273.15 does turn the bed heater to off but it leaves its active temperature (and probably also the standby temperature) at the last set value.
Is this difference intented?

It probably wasn't intended, but I don't think it's unreasonable behaviour.

I've never liked using -273.15 to turn heaters off, IMO there should be a more direct way.

[wilriker]

@dc42 said in [RRF 2.02] M703 blocking or async?:

I've never liked using -273.15 to turn heaters off, IMO there should be a more direct way.

Same here.