I am having a really odd issue that is difficult to diagnose. I *think* it is a Smoothie issue but I can't be sure. Here is the sequence:
1. Starting printing something. Hotend temperature rises to set point (e.g. 220C) and the print starts
2. Stop the print mid-print
3. Do something for a bit (e.g. fix a knot in the filament spool). Hotend cools down a bit (e.g. 100C)
4. Start a print (doesn't have to be the same job). Hotend temperature asymptotically approaches set point but never reaches it (e.g. 219C). Print never starts.
5. Power cycle the Smoothieboard and re-start the print. Print starts and runs fine.
Note: If I run the print to completion (i.e. don't stop it in the middle) then I don't get this issue.
Also before you ask, yes I have auto-tuned the PID multiple times. No difference.
My best guess is that the code executed to stop the print is causing the Smoothieboard to get into a weird state. Here is what it executes:
M104 S0 ; turn off extruder
M140 S0 ; turn off bed
M84 ; disable motors
But as far as I know this is exactly the same code that it executes when the print finishes. So I'm stumped.
Thanks in advance.