Complete Guide to the SIM800L GSM Module
A hands-on guide to the SIM800L GSM module: how to power it correctly — the real sticking point, where almost everyone gets stuck — how to wire and program it with Arduino using a voltage divider for logic-level adaptation, how to read network status through the key AT commands, how to handle sleep and wake-up, and how to send an SMS. Includes the wiring schematic, a complete sketch, a table of the pins used, and an FAQ section built from readers’ most common questions.