Ok hoping for some guidance from those of you that delve deeper into Marlin than I. Everything bellow is my Guesses… Either I suck at finding the right Marlin Documentation, or it just doesn’t exist…
Forgive me if this is long and rambly, but even if I do give up on Archim (and buy the SKR?), I’d like to understand Marlin a bit better…
Looking at
V1CNC_Archim1-2.0.7.2-src/Marlin/buildroot/share/PlatformIO/variants/archim/variant.cpp
It looks like PWML4-7 are enabled for PWM on channels 4-7:
{ PIOC, PIO_PC24B_PWML7, ID_PIOC, PIO_PERIPH_B, PIO_DEFAULT, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM), NO_ADC, NO_ADC, PWM_CH7, NOT_ON_TIMER }, // PWML7
{ PIOC, PIO_PC23B_PWML6, ID_PIOC, PIO_PERIPH_B, PIO_DEFAULT, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM), NO_ADC, NO_ADC, PWM_CH6, NOT_ON_TIMER }, // PWML6
{ PIOC, PIO_PC22B_PWML5, ID_PIOC, PIO_PERIPH_B, PIO_DEFAULT, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM), NO_ADC, NO_ADC, PWM_CH5, NOT_ON_TIMER }, // PWML5
{ PIOC, PIO_PC21B_PWML4, ID_PIOC, PIO_PERIPH_B, PIO_DEFAULT, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM), NO_ADC, NO_ADC, PWM_CH4, NOT_ON_TIMER }, // PWML4
Pins 35, 37, 39, 40, and 44 look like they are PWM capable but are commented out( CH 0,1,2,3,5):
{ PIOC, PIO_PC3, ID_PIOC, PIO_OUTPUT_0, PIO_DEFAULT, PIN_ATTR_DIGITAL, NO_ADC, NO_ADC, NOT_ON_PWM, NOT_ON_TIMER }, // PIN 35
//{ PIOC, PIO_PC3B_PWMH0, ID_PIOC, PIO_PERIPH_B, PIO_DEFAULT, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM), NO_ADC, NO_ADC, PWM_CH0, NOT_ON_TIMER }, // PWMH0 PIN 35
{ PIOC, PIO_PC5, ID_PIOC, PIO_OUTPUT_0, PIO_DEFAULT, PIN_ATTR_DIGITAL, NO_ADC, NO_ADC, NOT_ON_PWM, NOT_ON_TIMER }, // PIN 37
//{ PIOC, PIO_PC5B_PWMH1, ID_PIOC, PIO_PERIPH_B, PIO_DEFAULT, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM), NO_ADC, NO_ADC, PWM_CH1, NOT_ON_TIMER }, // PWMH1 PIN 37
{ PIOC, PIO_PC7, ID_PIOC, PIO_OUTPUT_0, PIO_DEFAULT, PIN_ATTR_DIGITAL, NO_ADC, NO_ADC, NOT_ON_PWM, NOT_ON_TIMER }, // PIN 39
//{ PIOC, PIO_PC7B_PWMH2, ID_PIOC, PIO_PERIPH_B, PIO_DEFAULT, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM), NO_ADC, NO_ADC, PWM_CH2, NOT_ON_TIMER }, // PWMH2 PIN 39
{ PIOC, PIO_PC8, ID_PIOC, PIO_OUTPUT_0, PIO_DEFAULT, PIN_ATTR_DIGITAL, NO_ADC, NO_ADC, NOT_ON_PWM, NOT_ON_TIMER }, // PIN 40
//{ PIOC, PIO_PC8B_PWML3, ID_PIOC, PIO_PERIPH_B, PIO_DEFAULT, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM), NO_ADC, NO_ADC, PWM_CH3, NOT_ON_TIMER }, // PWML3 PIN 40
{ PIOC, PIO_PC19, ID_PIOC, PIO_OUTPUT_0, PIO_DEFAULT, PIN_ATTR_DIGITAL, NO_ADC, NO_ADC, NOT_ON_PWM, NOT_ON_TIMER }, // PIN 44
//{ PIOC, PIO_PC19B_PWMH5, ID_PIOC, PIO_PERIPH_B, PIO_DEFAULT, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM), NO_ADC, NO_ADC, PWM_CH5, NOT_ON_TIMER }, // PWMH5 PIN 44
and our good friend Pin 53 looks like it’s not setup for PWM.
{ PIOB, PIO_PB14, ID_PIOB, PIO_OUTPUT_0, PIO_DEFAULT, PIN_ATTR_DIGITAL, NO_ADC, NO_ADC, NOT_ON_PWM, NOT_ON_TIMER }, // PIN 53
Then looking at the pin map:
My guess is:
PWML4-7 for PWM on channels 4-7 are used by:
HEATER_0_PIN, HEATER_1_PIN, HEATER_2_PIN, HEATER_BED_PIN
Pins 35, 37, 39, 40, and 44 (commented out CH 0,1,2,3,5):
Unused, X_MS3_PIN, X_MS1_PIN, X_STEP_PIN, Z_MS1_PIN
Now, I’m searching for a 5v logic PWM pin… My guess is that the heater pin’s are going to be input voltage (24V for me.). That probably means re-using one of the first 4 is out…
So I think that leaves 2 choices:
- Use pin 35 which is channel 0 (I seem to remember that Chanel 0 is reserved for something special???)
or
- Try to enable pin 53 for PWM (but what channel # should it be?)…