Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Use stock FAN #19

Open
mika54800 opened this issue Jun 25, 2020 · 1 comment
Open

Use stock FAN #19

mika54800 opened this issue Jun 25, 2020 · 1 comment

Comments

@mika54800
Copy link

Hello,

First of all thank you for the firmware, I use it on my MK3S it's great everything is well configured.

I did not want to change the fan of mine because ultimately it is completely compatible with the SKR 1.4 TURBO.

To be able to use it, I replaced in "pins_BTT_SKR_common.h" the value #define FAN_PIN P2_03 by #define FAN_PIN P1_24.
I actually use the PIN PWM of NEOPIXEL and it works perfectly.

Connect the red wire to pin P1_24, the black to the GND and the yellow remains unused.

@ruedli
Copy link

ruedli commented Jul 24, 2020

@mika54800

Taking PIN PWM for controlling a fan might not be a good idea, this pin is not driven by a MOSFET, but an 74LVC1G125, which is rated for 50mA and 250mW. It is meant as a BUS Driver, which makes sense for the Neopixel data.

Also, at one point, I will install NeoPixels, so I'll use FAN0 adapted to 5V as well as the E1 (as I am only using extruder E0), for the extruder cooling so:

I will do the following:

  • Both fans will be hooked up for their positive wire to +5V (from 5V or NPWR or a separate voltage regulator, making power for the fans)
  • Negative wire for part cooling fan: Pin1 of FAN0, this is pwm controled by FAN_PWM, which is pin 70 or P2.3/PWM1.4
  • Negative wire for hotend cooling fan: Pin2 of E1, this is pwm controlled by HE1_PWM, which is pin 69 or P2.4/PWM1.5

The positive wire is not taken from the sockets, as the other pins in these connectors or connected to VBB=24V (Pin2 of FAN0 and pin1 of E1).

There is no need to "redefine" any pins, as in pins_BTT_SKR_common.h, pin P2_04 is already defined as FAN1_PIN when you only use one hotend... Also P2.03 for FAN0, but this is less surprising. Clearly extruder1 is meant to be used as fan driver for system with one heated extruder.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

2 participants