Reply To: MPCNC 2.8w $100 laser add-on complete

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Hi, am new in this Forum and i have a question regarding the TTL-pins. Normally the fan is connected to PIN9. It is possible to add a pin (44) additionaly to pin 9, so both pins emit the same PWM-value? I dont’ want to use different firmwares for 3D-Printing and Laser-Cutting.
What i did until now: I searched the code to “DEFINE FAN_PIN 9”, then i added a “DEFINE LASER_PIN 44”. In the “planner.cpp” i inserted just after “analogWrite(FAN_PIN, CALC_FAN_SPEED(0));” the line
“analogWrite(LASER_PIN, CALC_FAN_SPEED(0)).
This should create a PWM-Signal on pin 9 and pin 44. The Signal on pin 9 is o.k. (I can regulate the fan speed on D9 and D44 with M106 Sxxx).
On pin 44 i have a PWM-Signal but only halve the value of the Signal on on D9.
For example “M106 S256” creates a PWM-Voltage of 5V ( respectively 12V after the mosfet), on pin 44 i measure only 2,5 Volts. Any suggestions why this has happened?

Greetings from Bavaria