A6 Mini GPRS/GSM Module Board with Antenna and Sim Card Slot Quad Band 850 900 1800 1900 MHz User’s Guide

Product Overview

• Module: Ai‑Thinker A6 Mini GSM/GPRS
• Bands: Quad‑band GSM 850 / 900 / 1800 / 1900 MHz
• Functions: SMS, voice calls, GPRS data (TCP/IP)
• Interfaces: UART (2.8–3.3 V logic), audio (MIC/earphone), SIM slot
• Power: 5 V input (≥2 A recommended), onboard regulator ~4.1 V
• Antenna: External helical antenna

Pinout Reference

Here’s the text‑based pinout mapping from the board:

• Left Side Pins
  • MTX / HRX: Secondary UART (often unused)
  • URX / UTX: Primary UART RX/TX (connect to MCU TX/RX)
  • E_R / E_L: Earphone right/left audio outputs
  • MIC2_P / MIC2_N: Secondary microphone input
• Right Side Pins
  • VCC: 5 V power input (≥2 A supply)
  • GND: Ground
  • IO14: General purpose I/O (can be used for control)
  • NET: Network status LED pin
  • PWR: Power key (pull low to turn ON/OFF)
  • INT: Interrupt pin (network events)
  • RST: Reset (active low)
  • MIC_P / MIC_N: Primary microphone input

Setup Instructions

1. Insert SIM Card
   • Use a standard GSM SIM (2G capable).
   • Place into the onboard SIM slot.
2. Power the Module
   • Connect VCC → 5 V, GND → Ground.
   • Use a stable supply (≥2 A).
3. Connect to Arduino/MCU
   • UTX → Arduino RX
   • URX → Arduino TX
   • GND → GND
   • Use SoftwareSerial at 9600 baud.
4. Test with AT Commands
   cpp

   #include <SoftwareSerial.h>
   SoftwareSerial gsm(11, 10); // RX, TX
   
   void setup() {
     Serial.begin(9600);
     gsm.begin(9600);
     gsm.println("AT"); // Test command
   }
   
   void loop() {
     if (gsm.available()) Serial.write(gsm.read());
     if (Serial.available()) gsm.write(Serial.read());
   }
   

Common AT Commands

• Check SIM: AT+CCID
• Signal strength: AT+CSQ
• Send SMS:
  Code

  AT+CMGF=1
  AT+CMGS="+639XXXXXXXXX"
  > Hello from A6! ␛ (Ctrl+Z)
  

• Make a call: ATD+639XXXXXXXXX;
• Answer call: ATA
• Hang up: ATH

Best Practices

• Use a stable 5 V/2 A supply.
• Ensure your SIM supports 2G GSM.
• UART logic is 2.8–3.3 V; use level shifters with 5 V MCUs.
• Keep antenna connected for reliable signal.

Applications

• SMS‑based alerts (alarms, monitoring)
• Voice call control (remote switching)
• IoT telemetry via GPRS (HTTP/TCP/IP)
• DIY GSM phone projects