Need help with pins for i/o - how I can set them? (no replies)

I am working on this issue already for some weeks, and so far no luck.

I am using Fysetc Spider v2.3 (they don't react to support questions) and I need some pins for switching externals (that is 3 pumps). I.e. for switches I I set in *_adv.h >

#define CUSTOM_USER_BUTTONS 
#if ENABLED(CUSTOM_USER_BUTTONS)
 #define BUTTON1_PIN PC9 // is pin 66
  #if PIN_EXISTS(BUTTON1)
    #define BUTTON1_HIT_STATE     HIGH      // tried LOW too
    #define BUTTON1_WHEN_PRINTING false     // Button allowed to trigger during printing?
    #define BUTTON1_GCODE         "G0 X5"
    #define BUTTON1_DESC          "Move X 5"  // Optional string to set the LCD status
  #endif

For the pumps etc. I set in *.adv.h

#define DIRECT_PIN_CONTROL
#define CUSTOM_1 PA8  // 67

And then try to set state with `M42 P66 S255` (Tried all the numbers incl. S0m S1, T0, T1 in all combinations.)

Pumps are connected to 5V and 24V via a mosfet breakout module.

On the web I found no instruction, so I hope to get some hints here.

BTW, I am using Marlin 2.1.x