BL Touch working on RRF2 but not RRF3

[CNCModeller]

Hi All,
I recently swapped over to RRF3 on my Duet ethernet and couldn't get my clone bltouch to work.

My main confusion is that the heater 3 pwm output drives an RC servo fine, and the bltouch responds properly to an RC servo tester. But RRF3 won't extend the bltouch, yet they worked together on RRF2.

Is it possible that I just need to convert the heater 3 pwm to a 5v signal? I can do this, but didn't get why changing from RRF2 to 3 would result in this different behaviour.

Any constructive thoughts would be much appreciated.

Cheers
Barry M

[droftarts]

@cncmodeller No, you don't need to change the signalling. If the probe is doing it's self-test at powerup, it's probably your deployprobe.g and retractprobe.g files, which are called by M401 and M402 respectively. So check if they work. To check your config.g, see
https://duet3d.dozuki.com/Wiki/Connecting_a_Z_probe#Section_Software_setup_RepRapFirmware_Num_3
To check the deployprobe.g and retractprobe.g files, see https://duet3d.dozuki.com/Wiki/Connecting_a_Z_probe#Section_Commissioning_Testing_RepRapFirmware_Num_3

Post your config.g, deployprobe.g and retractprobe.g files, and response to M115 (for firmware version) if you are still struggling.

Ian

[CNCModeller]

@droftarts

OK so this is weird (and annoying I've lost hours to this fault), all I've done is checked the BLTouch and the signals from the duet with a servo tester and a servo respectively (as above), and now I've re-connected the BLtouch and everything works...

I guess I might have had a "sticky" BLTouch???!

Also, for checking probing I decided to use a sponge to help prevent crashes, works a treat would recommend!!

All the best,
Barry M