background image

This sketch is set up to use a pre-defined stream – 
DJjNowwjgxFR9ogvr45Q. Feel free to use that for testing, but don’t abuse it 
or rely on it too much (it’s very possible our powers combined will exceed 
the post limit). This example gathers the Arduino’s analog pin values and 
posts all six of them to the stream.

To run the sketch, open the serial monitor and send any character to start a 
post.

Any response from the HTTP server will be routed back out to the serial 
monitor. Look for “HTTP/1.1 200 OK” to verify that the post was successful. 
You should also see an updated set of numbers on the stream page.

As the sketch continues to run, you can send another character over serial 
to initiate a new post. Just take care to only send one character at a time – 
and don’t abuse the strem!

Memory Limitations

The MG2639 library can really test the limits of the Arduino’s memory. 
You’ll notice that in most of these examples we put large, constant strings 
in flash (e.g. 

Serial.println(F("Hello, world"));

). In this example we’re 

also storing the Phant field strings in flash.

You’ll notice that most of these examples sacrifice flash storage space for 
as much SRAM as we can get. If your sketch mysteriously resets, or isn’t 
working as you’d expect, you may be running out of memory. It can be a 
diabolically hard problem to diagnose and fix, but start with trying to 
eliminate big strings and large arrays.

Resources & Going Further

We hope you’ll enjoy creating with the MG2639 Cellular Shield. If you have 
any questions about the board itself, these resources may be helpful:

• MG2639 Cellular Shield GitHub Repository
• MG2639 AT Command Manual
• MG2639 Hardware Design Manual

Page 21 of 22

Summary of Contents for MG2639 Cellular Shield

Page 1: ...whether it s a text message triggered MP3 player an environmental monitor logging to data sparkfun com or a new iteration of the Port O Rotary telephone Covered In This Tutorial This tutorial aims to...

Page 2: ...requires more power than an Arduino can supply when it s powered over USB We recommend this 9V wall adapter but any power supply within your Arduino s specified input voltage range should work SIM Ca...

Page 3: ...eld if you ve never installed a library before check this guide out Hardware Overview Before you get to connecting the MG2639 Cellular Shield to your Arduino you should familiarize yourself with the f...

Page 4: ...use with SoftwareSerial Instead we recommend using the AltSoftSerial library with this part of the module Either of the two UARTS the cell or GPS can be switched over to the Arduino s hardware UART Ch...

Page 5: ...B0104 level shifter It defaults to 5V but can be switched to 3 3V if your application requires Cellular UART RX and TX These jumpers allow you to switch the cellular module s RX and TX between either...

Page 6: ...rduino s unused pins You can also instead use male headers to connect it to the Arduino If you re looking to use the shield as more of a breakout board you can solder wires directly to the pins you ne...

Page 7: ...e SIM card into the shield The workings of the SIM card socket can take some getting used to To unlock the latch push the top part of the assembly towards the battery then lift it up Slide the SIM car...

Page 8: ...nding a suitable SIM card the most important part of getting the MG2639 Shield working is supplying it with enough power Power Supply Requirements Depending on which state it s in the MG2639 module ca...

Page 9: ...d to cut SJ2 and short SJ3 Jumper configuration for battery power Cut SJ2 and short SJ3 then clean it up better than we did SJ2 will prevent the 3 8V regulator from supplying a competing voltage to th...

Page 10: ...lar Shield library depends on Download and Install the Arduino Library We ve written an Arduino library specifically for the MG2639 Cellular Shield Click the button below to download it or clone it fr...

Page 11: ...s include SFE_MG2639_CellShield h To begin communication the cellular module and perform some set up call the cell begin function This initializing function will return with the status of the module a...

Page 12: ...ch for help using those functions Example 1 Text Messages The library includes a fun example sketch the demonstrates how to send and receive text messages If your cellular plan has SMS ability give th...

Page 13: ...rduino will send an SMS back to the sender with the desired information Using the Library SMS To use the SMS functionality of the library there is a second object defined as sms There are a variety of...

Page 14: ...message sending phone and timestamp the message was sent These values are only updated after an sms read Here s an example based on the sketch Get first available unread message int messageIndex sms a...

Page 15: ...ad allows you to go through the logs of your text messages and delete any or save them Example 2 GPRS TCP One of the most powerful aspects of the MG2639 is its ability to connect to a GPRS network and...

Page 16: ...ion can take a while to return successfully upwards of 30 seconds if the module is just getting warmed up so be patient If you ever need to turn GPRS off use the gprs close function This function has...

Page 17: ...connect to SparkFu n else if connectStatus 2 Serial println Received an error trying to connect Sending and Receiving As with other stream classes print write available and read functions are defined...

Page 18: ...ve voice calls If you re using a passive microphone and speaker you can simply connect them to the differential pins on the audio port Connect the microphone pins to MIC and MIC and speaker wires to S...

Page 19: ...G An outgoing call is in the process of dialing This status precedes ringing CALL_DIALED_RINGING An outgoing call has been dialed and is ringing on the other end CALL_INCOMING A call is coming in If a...

Page 20: ...t while phoneStatus CALL_ACTIVE phoneStatus CALL_ IDLE if callStatus CALL_ACTIVE Serial println Other end picked up Again you can use phone hangUp to end the call unless the other party does so first...

Page 21: ...e character at a time and don t abuse the strem Memory Limitations The MG2639 library can really test the limits of the Arduino s memory You ll notice that in most of these examples we put large const...

Page 22: ...ar Shield should serve as a solid launching point Serial Graphic LCD Hookup Learn how to use the Serial Graphic LCD Graphic LCD Hookup Guide How to add some flashy graphics to your project with a 84x4...

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