Features:
This module requires a 3.3 volt supply for VCC, and 3.3V logic.
Connecting RX or TX on 5V Arduino will destroy this module.
You must use a logic level converter, or a 3.3V Arduino.
The 3.3V supply on the Arduino Uno has inadequate current capability to power this module.
You must provide a separate, higher 3.3V supply(about 300mA or better).
TTGO T-Call V1.4 ESP32 SIM800L GSM Module
Transform your projects with the TTGO T-Call V1.4, a powerful ESP32-based GSM module that combines robust connectivity and versatile functionality. Ideal for IoT applications, this module integrates a SIM800L GSM/GPRS module with the ESP32 microcontroller, enabling seamless communication and data transfer.
ESP8266 offers a complete and self-contained Wi-Fi networking solution, allowing it to either host the application or to offload all Wi-Fi networking functions from another application processor. When ESP8266 hosts the application, and when it is the only application processor in the device, it is able to boot up directly from an external flash. It has integrated cache to improve the performance of the system in such applications, and to minimize the memory requirements. Alternately, serving as a Wi-Fi adapter, wireless internet access can be added to any microcontroller-based design with simple connectivity through UART interface or the CPU AHB bridge interface.