ESP32 with Sim800L

📶 ESP32 with SIM800L GSM/GPRS Module – IoT Combo for Wireless Communication

Overview:

The ESP32 is a powerful microcontroller with Wi-Fi and Bluetooth, and when paired with the SIM800L, it can also send SMS, make calls, or connect to the internet via GSM (2G). This combo is perfect for remote IoT projects, home automation, tracking, or SMS-based control.

SIM800L Key Specs:

• GSM/GPRS module (2G only)
• Supports SMS, voice, and HTTP (via GPRS)
• Operating Voltage: 3.7V–4.2V (⚠️ Do NOT power it directly from 5V or 3.3V ESP32 pins!)
• Baud Rate: 9600 (default, adjustable)

 Wiring ESP32 to SIM800L (via SoftwareSerial or HardwareSerial):

SIM800L Pin	ESP32 Pin
VCC	4.0V Regulated (not direct from ESP32!)
GND	GND
TX	GPIO16 (RX2)
RX	GPIO17 (TX2)

Use HardwareSerial(2) or SoftwareSerial for ESP32 depending on pins used.

 Power Supply Warning:

• SIM800L needs stable 4.0V – 4.2V at >2A burst current
• Use a Li-ion battery, buck converter, or external supply
• Add capacitors (1000µF or more) for stability

 Common Uses:

• SMS alerts (motion detection, alarms)
• GSM-based remote control
• GPS tracking (with added GPS module)
• HTTP GET/POST to send sensor data over cellular