Hey everyone,
I have installed my BLTouch sensor today. I have used the settings provided in the thingiverse objects, but I don’t think it is behaving correctly. First of all, it is homing at the very front left corner of the printer; thus missing the bad and it ends up crashing into the bottom of the printer. Second of all, I do not completely understand what the M119 command is supposed to give me. Most of the times it says:
x_min: open
y_min: open
z_min: open
z_probe: open
But sometimes it also says:
x_min: TRIGGERED
y_min: TRIGGERED
z_min: open
z_probe: open
To me it seems that it doesn’t make a difference.
First of all, you need to compile and upload a new version of Skynet3D. You must activate the „safe homing“ in the configuration.h, this way it will home Z in the middle of your printbed
1 Like
I am so terribly sorry for my late reply! I went on an unplanned vacation.
I guess I am back to square one, I tried to do everything over again from scratch but this time with autoleveling and safe homing activated, but now I get this error message.
“The given RIGHT_PROBE_BED_POSITION can’t be reached by the Z probe.”
These are my settings:
X_PROBE_OFFSET_FROM_EXTRUDER -45
Y_PROBE_OFFSET_FROM_EXTRUDER -9
Z_PROBE_OFFSET_FROM_EXTRUDER 0
define X_MAX_POS 250
define X_MIN_POS -13
define Y_MAX_POS 220
define Y_MIN_POS -13
define Z_MAX_POS 250
define Z_MIN_POS 0
define LEFT_PROBE_BED_POSITION 27
define RIGHT_PROBE_BED_POSITION 205
define BACK_PROBE_BED_POSITION 200
define FRONT_PROBE_BED_POSITION 20
Hi FistFull,
no problem 
First of all, to answer your former question: The M119 command is for checking the triggers. This way you can manually receive the current state of the triggers, before you do an Auto Home and the head will potentially crash into your bed. I used this command to test if my capacitive sensor is working correctly before I did my first Auto Home.
Now your other question: It is all about calculation. Lets assume you are the printer and want to reach the RIGHT_PROBE_BED_POSITION at 205. This would mean you would need to get the head to position 250 which is the Max position you set in your code. Marlin/Skynet also implements so called software endstops which are trigger here, because, as I think, the software trigger is checking if the target position is smaller than the max position, not smaller or equal. Try to set the Max position to 251 or disable the software endstops in the configuration (Danger: This could damage your hardware).
Search for “MAX_SOFTWARE_ENDSTOPS”
I also attached my current configuration.h as a reference. I am also using auto bed leveling with a sensor. Just rename the JPG to H
configuration.jpg (0 Bytes)
