Mellow SB2040 issue with on-board extruder driver

[Hot Toddy]

Hi,

Noob to the forum. I have already searched threads on the Mellow Fly SB2040 canbus board but not found anything relating to my particular issue. Hoping someone can help.

I've just built a Voron Trident with an Octopus v1.1 main board, and went the canbus route with the Mellow SB2040. I have CanBoot and Kilpper installed and working successfully with a canbus speed set to 1,000,000. To not complicate matters, I chose to use the native Octopus tmc2209 driver to run the extruder while I got all the other steppers configured and working, along with the hotend heater, temp sensors and Klicky probe over canbus to the SB2040. All that is now working fine. I can home, tram the bed, heat the hotend and run PID calibration against the temp sensors.

I've now attempted to switch to controlling the extruder over canbus (using the native tmc2209 driver on the SB2040) and run into a rather strange issue. The control of the extruder over canbus works successfully, and runs the extruder in the right direction, but will only do so for one command. Thereafter, I have the reboot the firmware to control the extruder again. So I was able to successfully calibrate the extruder with a G1 E100 F100 command to push 100mm of fliament through it. But if I try running the command again I get nothing! Which leaves me at a bit of a loss, as I had concluded the canbus communication was configured correctly and working well.

I've loaded the 'can-utils' package on the Raspberry Pi and tried running 'canbusload' and 'candump' commands (as suggested at https://github.com/akhamar/voron_canbus_octopus_sb2040) but I really don't know what I'm looking at. Any suggestions as to what's going on with my setup, or what I can do to test/debug it, would be gratefully received.

Thanks

 

[Neil_I]

Can you share your extruder config in printer.cfg? Just want to compare as I have the same setup as you

 

[Hot Toddy]

Can you share your extruder config in printer.cfg? Just want to compare as I have the same setup as you

Here it is ...

 

[Hot Toddy]

Oops, her it is ...

 

[Neil_I]

I've compared against my config and the only differences that i can see, apart from thermistor type and a slightly lower run current, are :

microsteps: 32 I have this set to 16
stealthchop_threshold: 999999. I have this set to 0

Not sure if these are relevant to your issue but it might be worth trying them as a quick test

 

[Hot Toddy]

I've compared against my config and the only differences that i can see, apart from thermistor type and a slightly lower run current, are :

microsteps: 32 I have this set to 16
stealthchop_threshold: 999999. I have this set to 0

Not sure if these are relevant to your issue but it might be worth trying them as a quick test

Interesting. I only updated my stealthchop_threashold yesterday from 0 to 999999 simply based on the example given on Mellow’s GitHub info on the SB2040. It made no difference regarding my issue. I’ll have a try at changing the microsteps value but I suspect that’s fine because my calibration when extruding 100mm was spot on. Thanks for the response.