What does 'M106 P0 S[fan_speed_pwm]' do?

[SweHogelid]

In my starting script for my IDEX printer the two first rows are:
M106 P0 S[fan_speed_pwm]
M106 P1 S[fan_speed_pwm]

I can't figure out what [fan_speed_pwm] does?
Do I need to have those?

/Micke

[horst.w]

https://reprap.org/wiki/G-code#M106:_Fan_On

horst.w
GER

[SweHogelid]

Thank you, but it does not explain the [fan_speed_pwm]

[horst.w]

Google know it!

H.

[dkightley]

And here's a clue:

If you're still stuck...have a read of this: viewtopic.php?f=8&t=1959