I like to use store bought PIR motion sensors and have them trigger a Pam-1 relay due to their quality and being much safer. I’ve been using heks Door, Window and Push-button sketch with S_MOTION/S_DOOR. This way I only have to short one of the pins to ground.
Well today I took the multi button relay sketch and combined it with heks sketch allowing me to have multiple motions on one pro mini.
Here’s the sketch with two motions
/**
 * The MySensors Arduino library handles the wireless radio link and protocol
 * between your home built sensors/actuators and HA controller of choice.
 * The sensors forms a self healing radio network with optional repeaters. Each
 * repeater and gateway builds a routing tables in EEPROM which keeps track of the
 * network topology allowing messages to be routed to nodes.
 *
 * Created by Henrik Ekblad <henrik.ekblad@mysensors.org>
 * Copyright (C) 2013-2015 Sensnology AB
 * Full contributor list: https://github.com/mysensors/Arduino/graphs/contributors
 *
 * Documentation: http://www.mysensors.org
 * Support Forum: http://forum.mysensors.org
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 *******************************
 *
 * DESCRIPTION
 *
 * Simple binary switch example 
 * Connect button or door/window reed switch between 
 * digitial I/O pin 3 (BUTTON_PIN below) and GND.
 * http://www.mysensors.org/build/binary
 */
// Enable debug prints to serial monitor
#define MY_DEBUG 
// Enable and select radio type attached
#define MY_RADIO_NRF24
//#define MY_RADIO_RFM69
#define MY_NODE_ID 12
#include <SPI.h>
#include <MySensors.h>
#include <Bounce2.h>
#define SSR_A_ID 1   // Id of the sensor child
#define SSR_B_ID 2   // Id of the sensor child
const int buttonPinA = 2;
const int buttonPinB = 3;
int oldValueA = 0;
int oldValueB = 0;
bool stateA = false;
bool stateB = false;
Bounce debouncerA = Bounce();
Bounce debouncerB = Bounce(); 
// Change to V_LIGHT if you use S_LIGHT in presentation below
MyMessage msgA(SSR_A_ID, V_TRIPPED);
MyMessage msgB(SSR_B_ID, V_TRIPPED);
void setup()  
{  
  // Setup the button
  pinMode(buttonPinA, INPUT_PULLUP); // Setup the button Activate internal pull-up
  pinMode(buttonPinB, INPUT_PULLUP); // Setup the button Activate internal pull-up
  // After setting up the buttons, setup debouncer
  debouncerA.attach(buttonPinA);
  debouncerA.interval(5);
  debouncerB.attach(buttonPinB);
  debouncerB.interval(5);
}
void presentation() {
  // Register binary input sensor to gw (they will be created as child devices)
  // You can use S_DOOR, S_MOTION or S_LIGHT here depending on your usage. 
  // If S_LIGHT is used, remember to update variable type you send in. See "msg" above.
  present(SSR_A_ID, S_MOTION);
  present(SSR_B_ID, S_MOTION);   
}
//  Check if digital input has changed and send in new value
void loop()
{
  debouncerA.update();
   // Get the update value
  int valueA = debouncerA.read();
  if (valueA != oldValueA) {
     // Send in the new value
     send(msgA.set(valueA==HIGH ? 0 : 1));
     oldValueA = valueA;
    
  }
 
  debouncerB.update();
  // Get the update value
   int valueB = debouncerB.read();
  if (valueB != oldValueB) {
     // Send in the new value
     send(msgB.set(valueB==HIGH ? 0 : 1));
     oldValueB = valueB;
  }
}```
Here's one with three motions
/**
 * The MySensors Arduino library handles the wireless radio link and protocol
 * between your home built sensors/actuators and HA controller of choice.
 * The sensors forms a self healing radio network with optional repeaters. Each
 * repeater and gateway builds a routing tables in EEPROM which keeps track of the
 * network topology allowing messages to be routed to nodes.
 *
 * Created by Henrik Ekblad <henrik.ekblad@mysensors.org>
 * Copyright (C) 2013-2015 Sensnology AB
 * Full contributor list: https://github.com/mysensors/Arduino/graphs/contributors
 *
 * Documentation: http://www.mysensors.org
 * Support Forum: http://forum.mysensors.org
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 *******************************
 *
 * DESCRIPTION
 *
 * Simple binary switch example 
 * Connect button or door/window reed switch between 
 * digitial I/O pin 3 (BUTTON_PIN below) and GND.
 * http://www.mysensors.org/build/binary
 */
// Enable debug prints to serial monitor
#define MY_DEBUG 
// Enable and select radio type attached
#define MY_RADIO_NRF24
//#define MY_RADIO_RFM69
#define MY_NODE_ID 11
#include <SPI.h>
#include <MySensors.h>
#include <Bounce2.h>
#define SSR_A_ID 1   // Id of the sensor child
#define SSR_B_ID 2   // Id of the sensor child
#define SSR_C_ID 3   // Id of the sensor child
const int buttonPinA = 2;
const int buttonPinB = 3;
const int buttonPinC = 4;
int oldValueA = 0;
int oldValueB = 0;
int oldValueC = 0;
bool stateA = false;
bool stateB = false;
bool stateC = false;
Bounce debouncerA = Bounce();
Bounce debouncerB = Bounce(); 
Bounce debouncerC = Bounce();
// Change to V_LIGHT if you use S_LIGHT in presentation below
MyMessage msgA(SSR_A_ID, V_TRIPPED);
MyMessage msgB(SSR_B_ID, V_TRIPPED);
MyMessage msgC(SSR_C_ID, V_TRIPPED);
void setup()  
{  
  // Setup the button
  pinMode(buttonPinA, INPUT_PULLUP); // Setup the button Activate internal pull-up
  pinMode(buttonPinB, INPUT_PULLUP); // Setup the button Activate internal pull-up
  pinMode(buttonPinC, INPUT_PULLUP); // Setup the button Activate internal pull-up
  // After setting up the buttons, setup debouncer
  debouncerA.attach(buttonPinA);
  debouncerA.interval(5);
  debouncerB.attach(buttonPinB);
  debouncerB.interval(5);
  debouncerC.attach(buttonPinC);
  debouncerC.interval(5);
}
void presentation() {
  // Register binary input sensor to gw (they will be created as child devices)
  // You can use S_DOOR, S_MOTION or S_LIGHT here depending on your usage. 
  // If S_LIGHT is used, remember to update variable type you send in. See "msg" above.
  present(SSR_A_ID, S_MOTION);
  present(SSR_B_ID, S_MOTION);
  present(SSR_C_ID, S_MOTION);   
}
//  Check if digital input has changed and send in new value
void loop()
{
  debouncerA.update();
   // Get the update value
  int valueA = debouncerA.read();
  if (valueA != oldValueA) {
     // Send in the new value
     send(msgA.set(valueA==HIGH ? 0 : 1));
     oldValueA = valueA;
    
  }
 
  debouncerB.update();
  // Get the update value
   int valueB = debouncerB.read();
  if (valueB != oldValueB) {
     // Send in the new value
     send(msgB.set(valueB==HIGH ? 0 : 1));
     oldValueB = valueB;
  }
  debouncerC.update();
  // Get the update value
   int valueC = debouncerC.read();
  if (valueC != oldValueC) {
     // Send in the new value
     send(msgC.set(valueC==HIGH ? 0 : 1));
     oldValueC = valueC;
  }
}```