Send and Receive SMS Using TTGO ESP32 SIM800L

Introduction

In Malaysia, project with GSM is still popular among students. I always search for simple and low cost solution for this application. Introduce TTGO ESP32 SIM800L board, that consists of WiFi, Bluetooth, GSM and GPRS in a single board. Plus, you can program it using Arduino IDE. So, today I would like to share how to get start with TTGO ESP32 SIM800L board and control relay through SMS.

Video

This video will show you how to get start with TTGO ESP32 SIM800L board and control relay through SMS.

Update 18 May 2022: I created a base for this tutorial so that the boards can be arranged more neatly.

Hardware Preparation

This is the list of items used in the video.

• TTGO T-Call ESP32 with SIM800L GPRS Module
• 1CH Active H/L 5V OptoCoupler Relay Module
• USB C to Type A Cable (1 Meter)
• 40-Way 10cm Jumper Wire (Male-Female)
• 3D printing products

Sample Program

This is Arduino sample program to control relay with SMS "RELAY ON" and "RELAY OFF". Please install 1 additional library at Arduino IDE Library Manager:

• Adafruit Fona Library by Adafruit Version 1.3.10

Thank You

References:

• Adafruit Fona Library - GitHub
• ESP32 SIM800L: Send Text Messages (SMS Alert) with Sensor Readings

Thanks for reading this tutorial. If you have any technical inquiries, please post at Cytron Technical Forum.