ESP32 with SIM900A GSM Module
📡 What is SIM900?The SIM900 is a GSM/GPRS module from SIMCom. It allows microcontrollers like ESP32 or Arduino to:✅ Send/receive SMS✅ Make/receive phone calls✅ Connect to the Internet (GPRS)✅ Send data to servers via HTTP, MQTT, TCP/IPIt communicates via UART (TX/RX) and uses AT commands.📦 Features of SIM900FeatureDescriptionNetwork2G GSM (850/900/1800/1900 MHz)CommunicationUART (AT commands)Baud RateDefault 9600SIM CardStandard-size SIM (2G supported)Power Supply5V–12V, 2A recommendedAntennaRequired for GSM signalOptionalMic & Speaker (for calls)🔌 SIM900 to ESP32 ConnectionSIM900 PinESP32 PinTXGPIO 16 (ESP32 RX)RXGPIO 17 (ESP32 TX)GNDGNDVCC⚠️ External 5V 2A power supply⚠️ DO NOT power SIM900 directly from ESP32 or USB....
