[BUG] MKS-GEN_L (V 1.0) pins config error for double extruder setup

[aegelsky]

Did you test the latest bugfix-2.0.x code?

Yes, and the problem still exists.

Bug Description

when using in Configuration.h:

#define MOTHERBOARD BOARD_MKS_GEN_L
#define EXTRUDERS 2

it uses pins_MKS_GEN_L.h, which in turn uses pins_RAMPS.h,
where FET_ORDER_EEB is selected (which is right), but pins in RAMPS and MKS GEN L don't match in second extruder:

#elif FET_ORDER_EEB // Hotend, Hotend, Bed
#define HEATER_1_PIN MOSFET_B_PIN
#define HEATER_BED_PIN MOSFET_C_PIN

#elif FET_ORDER_EEB // Hotend, Hotend, Bed
#define FAN_PIN 4 // IO pin. Buffer needed

(from pins_RAMPS.h)

this leads to:
HEATER_1_PIN = 9
FAN_PIN = 4

and here is actual MKS GEN L pins map:
/~https://github.com/makerbase-mks/MKS-GEN_L/blob/master/hardware/MKS%20Gen_L%20V1.0_008/MKS%20Gen_L%20V1.0_008%20PIN.pdf

pin D9 is fan pin and D4 is servo pin, so when enabling second extruder heater, fan turns ON and there is no way to power on fan.
(also I wouldn't power up extruder heater from fan socket, it very possibly might no handle 40W output)

adding this into pins_MKS_GEN_L.h (from line 40) fixes this issue:

// Hotend, Hotend, Bed + Fan on D9
#if FET_ORDER_EEB
#define MOSFET_B_PIN 7
#define FAN_PIN 9
#endif

just trying to help the community.

Bug Timeline

old (I guess)

Expected behavior

adding MKS GEN L motherboard uses valid pins

Actual behavior

pins for extruder 2 and fan are messed up

Steps to Reproduce

#define MOTHERBOARD BOARD_MKS_GEN_L
#define EXTRUDERS 2

this leads to:
HEATER_1_PIN = 9
FAN_PIN = 4

which is wrong

Version of Marlin Firmware

2.0.x (2.0.9.3)

Printer model

Prusa i3

Electronics

MKS GEN L V 1.0

Add-ons

second extruder

Bed Leveling

No response

Your Slicer

No response

Host Software

No response

Additional information & file uploads

adding this into pins_MKS_GEN_L.h (from line 40) fixes this issue:

// Hotend, Hotend, Bed + Fan on D9
#if FET_ORDER_EEB
#define MOSFET_B_PIN 7
#define FAN_PIN 9
#endif

just trying to help the community.

[ellensp]

Want to try your hand at a PR? https://marlinfw.org/docs/development/getting_started_pull_requests.html

[aegelsky]

Want to try your hand at a PR? https://marlinfw.org/docs/development/getting_started_pull_requests.html

will try to find time for it in next few days..

[aegelsky]

Want to try your hand at a PR? https://marlinfw.org/docs/development/getting_started_pull_requests.html

I haven't used git for quite a long time, but looks like I finally made it here:
#23965

[ellensp]

PR looks fine. So closing this issue.

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.