ESP32 + SIMCOM 4G
Relay and GSM test panel
GPIO26 low trigger GSM control with two relay outputs for quick bench checking before connecting the irrigation dashboard.
4G
GSM pinHIGH
Active relays0/2
Signal18 CSQ
Built-in GSM
GPIO26 active LOW
Relay 1
GPIO25 active LOW
Relay 2
GPIO27 active LOW
Signal check
AT+CSQ expected above 10
GSM OFF