Basic Information:
Printer Model: Customized Ender3
MCU / Printerboard: BTT SKR E3 V2
Host / SBC: Atomic Pi
Describe your issue:
To preface: I consider this user error that allowed me to unconver what I consider a minor bug. Somehow in my machine g-code the following line:
M190
crept in. It occurred after the actual M190 S[Bed Temp] and M109[E0 Temp] commands. The effect is that the bed and nozzle would heat, and then the naked M190 would turn the bed heat offf.
Is this behavior on purpose? The Marlin docs say:
“Without any parameters M190 does nothing.”
This is likely how it crept into my slicer’s machine G-code, as in Marlin there was no deleterious effect of having it there. In Klipper, my bed would heat, my nozzle would heat, and the naked M190 command (issued just before homing) would then shut the bed off until the second layer, where I turn the temperature down by 5C. So basically the bed was off for the whole first layer.
This went on for a short bit, until I tried to print something with a huge first layer which allowed the bed to cool enough to the point where it stopped sticking and I got a failure. Troubleshooting the gcode led me to the root cause: M190 with no arguments does not behave consistent with Marlin.