Introduction: GSM SMS Relay Alternative Firmware.

An all-new alternative firmware for controlling two relays module.

User-friendly responses from the controller are now available.

Up to 7 users with different permissions can control the device (slots: AB01234).

Supplies

Dual relay SMS board based on stm32F030C8T6 with SIM800C module.

Can be found on most marketplaces.

Step 1:

Minimal soldering skills are required.

Connect an ST-LINK, burn the provided HEX file (or compile your own).

Then activate unit by sending SMS "activate" on it.

Step 2:

Connect serial @115200 to see and control some more functions.

See github for details and sources.