Getting started with ai thinker a7 module

Description about the module

This is a GPRS/GSM/GPS module, supports GSM/GPRS Quad-Band (850/900/1800/1900) network. Also, it supports voice calls, SMS messages, GPRS data service and GPS function. The module is in ebay, make sure to buy module with the development board. It will save your time. This is the link from which I bought the module here.

From this article I’m only going to tell you how to setup and work with a7‘s gsm feature, by which you will be able to call and receive a call, send and read received message.

With the package you will receive two antennas. They have provided short antenna for gsm, and the long one for gps. But for working with gps data this antenna will not help you much. And I will tell you more about it on my article about the GPS function of a7 module. At the moment you will only need the short antenna.

Pins and for what they are for

Refer the a7 module section of the official documentation provided by Ai thinker for a7 module. I have mentioned the link.

And you will need to know that you won’t be able to use the micro usb port for anything other than giving power to the module. If you look closely you will see that only two pins from micro usb port is taken into use, so the data sending and receiving pins are not connected to the module.

Setting up the module

Get the module and you will see the micro sim card holder in the backside of the module. Insert your sim to the tray and lock it.

To set the module up you will need an Arduino and several male female connectors. As in the figure im using a Arduino mega.

Download the code from here.

Map the pins as follow

URXD ------- > TX(arduino mega)

UTXD ------- > RX(arduino mega)

GND ------- > GND

Mic- ------- > - of the mic (of receiver)

Mic+ ------- > + of the mic (of receiver)

Rec- ------- > - of the speaker (of receiver)

Rec+ ------- > + of the speaker (of the receiver)

Micro usb ------- > power (simply connect to your laptop or an external 5v supply)

Powering up the module

First connect the Arduino to your pc (don’t turn on a7 module) and upload the code. Then open the serial monitor in Arduino ide and set baud rate to 115200. And set the mode to Both NL & CR.

Then press the power button in a7 module for about 2seconds, and the module will boot up. When the module is booted up properly you will see your serial monitor is giving you outputs. Below are some basic AT commands which I used to work with a7 module.

Type AT in the serial monitor and press enter. If its prints ok then you are good to go with at commands.

AT+CMGF=1 ------- > enter this command. If you get an error this means you have a pin for you sim, and you have to enter the pin to work with the sim

AT+CPIN=”XXXX” ------- > if you have a pin for your sim replace xxxx with it (else skip this command)

AT+CMGF? ------- > shows which mode messaging mode you are on

AT+CMGF=1 ------- > set this to one will put you in text messaging mode

AT+CMGS="94770866578"------- >to send a message. After this command you will be able to type your message in the terminal. If you have searched how to send a message with AT commands, you will get that press ctrl+z after typing the message. And some of you may have experienced that this is not working in Arduino serial monitor. So I have added a line in my code which will bypass this problem. Instead of ctrl+z you will have to type * symbol at the end of your message. Then it will send your message

AT+CSQ ------- >to check signal level

AT+CPBR=1,100 ------- > get first 100 contacts

AT A ------- > answer an incoming call

AT+CLCC ------- >get calling number

AT H[0] ------- > hangup an answered call

ATD9477xxxxxxx ------- > make a call

ATH ------- > disconnect call

Have fun!!!!!!!!!!