Invert Fan Signal for Low Level Triggering MOSFETS
Greetings,
I am using a 4 MOSFET board connected to pins 4, 5, 6, and 11 to control 3 extruder fans, and a part fan. The board in question this one: http://www.icstation.com/channel-field-effect-tube-module-nmos-fr1205-with-optocoupler-isolation-p-9821.html. I did not realize it at the time of purchase, but it uses low level trigger.
Is there a quick way to invert the signals to the pins? (If not, I would like to make it a feature request)
If there isn't one, where in the code would I find where the speed is set. I imagine that all I would need to do is change speed value from "n" to "255-n".
Best Regards,
PM8471
I am using a 4 MOSFET board connected to pins 4, 5, 6, and 11 to control 3 extruder fans, and a part fan. The board in question this one: http://www.icstation.com/channel-field-effect-tube-module-nmos-fr1205-with-optocoupler-isolation-p-9821.html. I did not realize it at the time of purchase, but it uses low level trigger.
Is there a quick way to invert the signals to the pins? (If not, I would like to make it a feature request)
If there isn't one, where in the code would I find where the speed is set. I imagine that all I would need to do is change speed value from "n" to "255-n".
Best Regards,
PM8471
Comments
#define HEATER_PINS_INVERTED 1
for fans there is no invert and you need to do this manually in HAL.cpp in PWM_TIMER_VECTOR, just search for HEATER_PINS_INVERTED and you should see how it is done.
But notice that this inherently dangerous! For heaters this means if you have no firmware like on upload or maybe only while testing or on wrong config the heaters are full power when you have main power. Using it for fans is safe since it is no big risk if a fan is on or off.
I'm not concerned about having inverted heater pins as I have the extruder heaters running off of the board's MOSFETS and the bed off of a relay.