Forcing Rotary Encoders on P20v2 PCB

Both P20v2 and P42 PCBs have net errors with its rotary encoders. Pin Bs and GNDs were interchanged. Removing PCB traces and re-wiring new ones will correct these. 

First, these are the current pin outs for P20v2 PCB (A C B):

Encoder 0: F4 F7 GND

Encoder 1: F5 B1 GND

Encoder 2: F6 B3 GND

Above pins should be:

Encoder 0: F4 GND F7 

Encoder 1: F5 GND B1

Encoder 2: F6 GND B3

Disclaimer: These steps may cause shorts, kill the PCB, or cause personal and/or property damage. Please proceed at your own risk.

Now that the proper pins were identified, we now have to remove existing trace/nets/connections of the encoders. I use a small knife to cut the traces:

The traces that needs to be disconnected are those shown in the following photos:

Back of PCB

Front of PCB

Photos of disconnected traces on mine:

Now that the connections were cut, it's time to place the traces to their proper pins.

Actual photos

...and here's a view from the back:

Middle pins of the encoders should all be connected to GND.

To activate these encoders, edit ver2/config.h and add the following:

#undef ENCODERS_PAD_A 

#undef ENCODERS_PAD_B 

#define ENCODERS_PAD_A { F4, F5, F6 } 

#define ENCODERS_PAD_B { F7, B1, B3 }

...then define roles of the encoders in ver2/keymap.c

void encoder_update_user(uint8_t index, bool clockwise) { 

if (index == 0) { /* First encoder */ 

  if (clockwise) { 

    tap_code(KC_A); 

  } else { 

    tap_code(KC_B); 

  } 

 } else if (index == 1) { /* Second encoder */ 

  if (clockwise) {  

    tap_code(KC_C); 

  } else { 

    tap_code(KC_D); 

  }  

 } else if (index == 2) { /* Third encoder */ 

  if (clockwise) { 

    tap_code(KC_E); 

  } else { 

    tap_code(KC_F); 

  }

 }

}




Compile. Flash. Enjoy!

Current P20v2 github repository.