Re-Arm Ramps 1.4 Laser Control

Setup
Re-Arm Board
Ramps 1.4 Shield
4W Laser Module
CoreXY
Smothieware

# Laser module configuration
laser_module_enable true # Whether to activate the laser module at all. All configuration is ignored if false.
laser_module_pin 2.7 # this pin will be PWMed to control the laser
laser_module_max_power 0.99 # this is the maximum duty cycle that will be applied to the laser
laser_module_tickle_power 0.0 # this duty cycle will be used for travel moves to keep the laser active without actually burning

But D8 on the Ramps stays at 12v does not very from 0v-5v
What am I doing wrong

If i am looking at the pinout correctly pin 2.7 is D8?

Edited 1 time(s). Last edit at 07/26/2019 10:21PM by oldtimmer.

D8 is 2.7

potentially your measuring it wrong.... as you have to measure from the D8 - pin to the D8 + pin, as gnd is switched so you can't use a common ground for measurements

D8 will output what ever voltage you feed into the 11amp power plug.

My Laser has 3 pins
Pin 1 - 12v
Pin 2 - GND
Pin 3 - TTL 0v - 5v 15kHz

So I need to find a 5v PWM

Edited 1 time(s). Last edit at 07/26/2019 11:13PM by oldtimmer.

Expecting a 5v signal on a 3.3v controller is asking a lot of this...

There are only 4 pins that are level shifted to 5v
He1 mosfet (gate pin)
He2 mosfet (gate pin)
HBed mosfet (gate pin)
P1.18LS

So you either need to solder a wire on the gate of the mosfets or
It does look like you can use the data pin on servo3 (d4 1.18) it should be 5v but i'm not sure if it does PWM correctly or not,,, Your going to have to try it.

Edited 1 time(s). Last edit at 07/27/2019 01:28AM by Dust.

servo4 (d4 1.18) is 5v
set (laser_module_pwm_pin 1.18)
Connected ttl from laser module to servo4 and it works(yeha lol)

Thank You all for the help