RAMPS 1.4 Marlin RC8 CONTROLLERFAN_PIN issue

Hello,

I am using Marlin 1.10 RC8 with RAMPS 1.4. Printer is custom-built Delta. Board configuration BOARD_RAMPS_14_EFB, with HEATER_BED_PIN assigned to pin 57.
I plan to use D8 output for aux fans control - RAMPS and hot end coolers.

In Configuration_adv.h I changed CONTROLLERFAN_PIN to 8, compilation goes fine, but then nothing happens. I assume 12V should appear at D8 pins when steppers begin to work, but it remains zero.

Have I missed anything or CONTROLLERFAN_PIN can't be assigned to D8?

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WBR,
Mikhail

The mosfet controls the ground side of the connection, the + side is always connected.

Thanks, just checked and see 12V between D8 + and ground. Yet the problem persists - always zero between D8+ and D8 -.

D8 isn't the cpu pin number, it's the name of the pin.

I believe you need to set CONTROLLERFAN_PIN to 57 and HEATER_BED_PIN to -1, to disable or whatever pin you're using for a heated bed.

Quote
stephenrc
D8 isn't the cpu pin number, it's the name of the pin.

As I can see on the RAMPS schematic, it is. [reprap.org]
If not, then which CPU pin D8 corresponds to?

Quote
stephenrc
I believe you need to set CONTROLLERFAN_PIN to 57 and HEATER_BED_PIN to -1, to disable or whatever pin you're using for a heated bed.

In my current configuration pin 57 controls heated bed relay. I can't use D8 output for heated bed because current is too high for RAMPS circuit. That's why I decided to use it for something useful that draws less current.
With proposed changes I won't be able to use heatbed at all.

Hello,
thanks for the help, problem is solved. The issue was in missing voltage at secondary power supply.