Pin and connectors

Analog input (pins 34, 35, 36, 39)
Digital input  (pins 27, 32)

Really on board 2   (pins 15, 12)
Buzzer pin (0)
ESP32 Reset default settings  pin(2)
IR pin(3)

Serieal connector  4pin (+5v, 4, 25, GND) 
Modbus Serieal connector  4pin (GND, 16, 17, +5V) 
Display 1.3” 4pin (+3v, GND, 22_CL, 21_DA)
CRT connector  5pin  (+3v, 21_D, 22_C, NC, GND)
GSM 6pin (RF, +4V, RS_33, RX_14, TX_13, GND)
Ethernet connectors 2x6pin (5, 18, 19, 23, 26)