Connecting a BLTouch or BTT MicroProbe to a Fly-Gemini-V2

Physical Connections

Connect the BLTouch to the Fly-Gemini-V2 as described in the table below.

Config.g Changes

Your config.g should be modified as below.

M558 P9 H6 F250:30 T8000 C"^probe"       ; set Z probe type to bltouch and the dive height + speeds
M950 S0 C"Servo0"                              ; Setup Servo0 as servo port on Fly-Gemini-V2

You will also need to set up your probe offset using G31 and your mesh probing grid

Files to Create

Create the following files.

deployprobe.g

Create a file in your sys folder called

deployprobe.g

In it, paste the following code

M280 P0 S10

retractprobe.g

Create a file in your sys folder called

retractprobe.g

In it, paste the following code

M280 P0 S90

Files to Modify

If you you want to use your probe as your z endstop, you need to modify your homeall.g/homedelta.g and homez.g

homez.g

For homez.g, you will have need to have something similar to this. Please modify the co-ordinates required for the centre of your bed accordingly.

; ################# Home Z Preparation ################

G91 															; Relative mode
G1 H2 Z5 F5000													; Lower the bed
G90																; Back to absolute positioning
G1 X0 Y0 F10000 		 										; Move to the center of the bed. Adjust to the co-ordinates required for the centre of your bed

; ################# Home Z Preparation ################

G30					 											; Probe a single point

homeall.g

The homeall.g should have something similar to the above or should call the homez.g file using

M98 P"homez.g"

Testing Macros

It is suggested that you create a number of macros to allow testing of your BLTouch. These should each be created in the macros folder.

alarm release + pin

Create a file in your macros folder called

alarm release + pin

In it, paste the following code

M280 P0 S160 ; Alarm Release and Push-Pin UP

pin up

Create a file in your macros folder called

pin up

In it, paste the following code

M280 P0 S90 ; Send PWM channel 0 the s90 (angle) command

pin down

Create a file in your macros folder called

pin down

In it, paste the following code

M280 P0 S10 ; Send PWM channel 0 the S10 (angle) command

selftest

Create a file in your macros folder called

self-test

In it, paste the following code

M280 P0 S120 ; Send PWM channel 7 the S10 (angle) command

Links to Relevant Duet3D Documentation

Connecting a BLTouch
Troubleshooting a BLTouch

Marlin Fast Probe

There is a guide to replicating Marlins Fast Probe feature here.

Troubleshooting

M280 works but the probe doesn’t deploy using G30

Test that the probe deploys and retracts using M401 and M402 respectively.
If they don’t work then you either have the deployprobe.g and retractprobe.g in the wrong place (they need to be in sys) or the contents of those files are incorrect, in which case re-read this page.

M280 doesn’t work

Either the wiring for the BLTouch is incorrect or the M950 servo definition is incorrect in config.g.

The probe doesn’t self test on Startup

The wiring for the BLTouch is incorrect and should be checked.

The probe doesn’t trigger

Either the wiring for the BLTouch is incorrect (swap the black and white cables) or the M558 definition is incorrect in config.g.