setting up bltouch z offset with SKR Mini e3 2.0 on ender3pro with existing z-switch

e3p-blt-z-offset.txt

All the videos that I found were about older boards or using the model where the bltouch replaces the z-end stop switch instead of augmenting it. I wanted to keep it as an extra failsafe so that I was not reliant on the soft switch to prevent a head crash.

Wire Bltouch to Probe port
Leave z end switch connected

Load firmware-bltouch.bin from https://github.com/bigtreetech/BIGTREETECH-SKR-mini-E3/tree/master/firmware/V2.0

note that the zhoming firmware only works if you replace the z end switch with the bltouch, so we won't use that. 

Z-Offset Instructions:
1. Move X and Y to +100 and heat the bed
2. M851 Z0 - Reset Z0Offset
3. M500 - Store setting to eeprom
4. M501 - Set active parameters
5. M503 - Display Active Parameters
6. G28 Z - Home Z Axis
7. G1 F60 Z0 - Move nozzle to true 0 offset
8. M211 S0 - Switch off soft endstops
9. Move nozzle towards bed slowly until the paper can barely move
10. Take note of the Z on the printer display (take that number and add the measurment of the calibration sheet or device used)
11. M851 Z X.XX (X.XX being your z offset achieved, and this should be negative)
12. M211 S1 - Enable Soft Endstops
13. M500 - Save settings to Eeprom
14. M501 - Set Active Parameters
15. M503 - display current settings