Several issues addressed in this PR:
- CutFilament tuning + error recovery
- introduce register 0x1d (cut filament selector iRun current level)
- optimize setting iRun and iHold currents in the FW
- CutFilament unit test fixed
With PWM_FREQ=2 (fPWM = 2/512 fclk), the idler parked current was quite high since the setting was not actually respected (scientifically tested using hand). In order to allow lower current regulation in stealthchop, TBL and PWM_FREQ need to be adjusted. The lower both of these values, the better. Since TBL affects both stealthchop and spreadcycle, I chose to only modify PWM_FREQ.
This new PWM_FREQ results in half the previous stealthchop PWM frequency and also halves the low current limit (so if previously the minimum achievable current was 300mA, now it would be 150mA). I confirmed that this setting works correctly on a 24V supply. There is no audible noise from stealthChop PWM and the hold current is indeed reduced now (again, scientifically tested using my hand).
This PR is just about tuning the intermediate Idler positions so that the filament gets relieved from the Pulley safely while the Extruder gears take over and the activeSlot+1 filament is not affected by its Idler bearing.
On a test bench filament was creeping about 0.5mm per Toolchange.
Changing the intermediate position from exact middle into 3/4 practically elliminated the creep. We can play with these constants more if necessary in the future.
- rename stall*guard to StallGuard (match name with the vendor)
- separate TMC2130 module from EEPROM (they do not need to know about each other at all)
- separate SGTHRS settings from motion - moved to globals like all other "global" parameters
- improved EEPROM storage for SGTHRS
This is to solve a potential problem while feeding to printer's drive gears - while disengaging the Idler, the Pulley was still rotating to avoid grinding the filament (printer is pulling it).
Other filaments could have moved a bit when the Idler's bearings ran over them while the Pulley was still rotating slowly -> the filament could have been moved into the Selector's path causing trouble (especially when not used in the print).
Therefore, the Idler disengages partially now - moves into an intermediate position between the slots.
Then, the Pulley is completely stopped and after that the Idler does a full disengage like before.
This solves a number of issues - if FINDA or FSensor failed,
the unload was never "complete" - filament was stuck in the selector
blocking it from normal operation.
Now, after all errors have been resolved, filament is explicitly FED
into FINDA and then RETRACTED to Pulley.
Slower loading speed is necessary for precise detection
of filament sensor trigger and starting rotation of the E-motor.
Experimentally it turned out speeds above 80mm/s tend to cause timing issues
(sometimes one can hear a crack as MMU' or the printer's drive gears
slip while pushing the filament).
Such a timing issue then causes blobs in purge towers.
On the other hand - 80mm/s for the fast part of filament load
seems not only absolutely reliable, but also very quiet.
120mm/s for unload is much louder (we may slow it down later)
In AVR __builtin_abs() breaks for non-base types.
Provide a generic function and use an overload when it is safe to use
instead.
This fixes the underlying step count calculation in PlanMove, thus
removing the need for the PlanLongMove work-around.
- fix homing procedure for Idler and Selector
(homing now ends with a move to the Parking position)
- fix unit tests' startup conditions with regard to necessary
homing of Idler and Selector
TODO: still test_cut_filament fails for minor reasons
That includes:
- introduce pulley slow feedrate and fsensor-to-nozzle distance
in config necessary for slowly feeding the filament from fsensor into the nozzle.
(the constant is subject to extraction into some other config as it has to be used in the printer as well).
- update FeedToBondtech accordingly to perform a gentle push into the nozzle
after fsensor detects the filament + update its unit tests.
- slight cleanup of LoadFilament + fix its unit tests
- add FeedingToNozzle progress code, as it might be interesting
to inform the printer about this task in the future
- revert non-clean changes from RetractFromFinda - it should not disengage the idler
- revert incorrect + fix ToolChange
- clean-up UnloadFilament
3d-gussner
D.R.racer
Alex Voinea
Yuri D'Elia