G30 dual speed probing with S<0

Serbitar

I hvae a bltouch configured and working with

M558 P9 C"^io1.in" B1 H5 F600:60 T6000

When homing Z i use G30 and as expected the probing is done once quickly and then more slowly in the second pass.

With my calibration macros i use G30 S-2 to set the probe z offset with this it only probes with the faster speed.

I am working around the problem by reconfiguring the probing speeds to F60 in the calibration macros.

Is this behaviour expected or a bug?

RepRapFirmware for Duet 3 Mini 5+ version 3.4.0 (2022-03-15 18:59:15) running on Duet 3 Mini5plus WiFi (SBC mode)

Serbitar

For extra fun, it seems M558 resets the X and Y values (but not Z) of the probe offset set in G31.

4/1/2022, 7:36:56 PM	G31
Z probe 0: current reading 0, threshold 500, trigger height 0.700, offsets X0.0 Y0.0 U0.0
4/1/2022, 7:36:38 PM	M558 P9 C"^io1.in" B1 H5 F60 T6000
4/1/2022, 7:36:25 PM	M558
Z Probe 0: type 9, input pin io1.in, output pin nil, dive height 5.0mm, probe speeds 60,60mm/min, travel speed 6000mm/min, recovery time 0.00 sec, heaters suspended, max taps 1, max diff 0.03
4/1/2022, 7:36:13 PM	G31
Z probe 0: current reading 0, threshold 500, trigger height 0.700, offsets X56.0 Y16.0 U0.0
4/1/2022, 7:36:10 PM	g31 x56 y16

fcwilt

@serbitar

From the documentation:

M558 with P parameter deletes the existing probe with that K number (if any) and creates a new Z probe. This resets the G31 values for that probe to default values.

Is that what you are seeing?

Frederick

dc42

@serbitar as @fcwilt says. When you want to change M558 parameters, leave out the P and C parameters and any others that you don't want to change. So in your example, M558 F60 or M558 K0 F60 is all you need to use to change the probing speed.

Serbitar

@fcwilt Thanks, for pointing that out. I should have read that doc more thoroughly.

I have also found a proper solution which is to specify M558 A2 (or higher) which causes all the G30 S-2 to probe slowly on the second (and third) probes.

I'm still surprised by the difference in behaviour between G30 and G30 S-2 in my previous configuration.