diff options
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/TMC_Drivers.md | 30 |
1 files changed, 17 insertions, 13 deletions
diff --git a/docs/TMC_Drivers.md b/docs/TMC_Drivers.md index cd705ae3..fee1e75a 100644 --- a/docs/TMC_Drivers.md +++ b/docs/TMC_Drivers.md @@ -258,10 +258,13 @@ After sensorless homing completes the carriage will be pressed against the end of the rail and the stepper will exert a force on the frame until the carriage is moved away. It is a good idea to create a macro to home the axis and immediately move the carriage away from the end -of the rail. It is recommended to set the speed of this subsequent -move so that it lasts at least two seconds (eg, `G1 X40 F1200`) to -ensure the stall flag in the TMC driver is cleared after the move -completes. +of the rail. + +It is a good idea for the macro to pause at least 2 seconds prior to +starting sensorless homing (or otherwise ensure that there has been no +movement on the stepper for 2 seconds). Without a delay it is possible +for the driver's internal stall flag to still be set from a previous +move. It can also be useful to have that macro set the driver current before homing and set a new current after the carriage has moved away. This @@ -279,11 +282,13 @@ gcode: {% set HOLD_CUR = driver_config.hold_current %} # Set current for sensorless homing SET_TMC_CURRENT STEPPER=stepper_x CURRENT={HOME_CUR} HOLDCURRENT={HOME_CUR} + # Pause to ensure driver stall flag is clear + G4 P2000 # Home G28 X0 # Move away G90 - G1 X40 F1200 + G1 X5 F1200 # Set current during print SET_TMC_CURRENT STEPPER=stepper_x CURRENT={RUN_CUR} HOLDCURRENT={HOLD_CUR} ``` @@ -308,16 +313,15 @@ sensitivity" for each carriage, but be aware of the following restrictions: 1. When using sensorless homing on CoreXY, make sure there is no `hold_current` in effect for either stepper during homing. -2. Make sure both the X and Y carriages are near the center of their - rails before each home attempt. +2. While tuning, make sure both the X and Y carriages are near the + center of their rails before each home attempt. 3. After tuning is complete, when homing both X and Y, use macros to ensure that one axis is homed first, then move that carriage away - from the axis limit using a move that lasts at least two seconds, - and then start the homing of the other carriage. The move away from - the axis helps ensure the stall flag is cleared from both stepper - drivers before starting the next home attempt. It also avoids - homing one axis while the other is pressed against the axis limit - (which may skew the stall detection). + from the axis limit, pause for at least 2 seconds, and then start + the homing of the other carriage. The move away from the axis + avoids homing one axis while the other is pressed against the axis + limit (which may skew the stall detection). The pause is necessary + to ensure the driver's stall flag is cleared prior to homing again. # Querying and diagnosing driver settings |