Go Down

Topic: Need recommendation on Arduino board and 3G shield (Read 290 times) previous topic - next topic

Hansen70

I would like recommendations on what model Arduino board and what model 3G shield to use for a remote 3G cellular switch.
Note: Digital output will run a 12vdc 100ma pump (or similar).
Device is battery powered so energy efficient design is needed.
I need them to be plug in to each other for assembly efficiency.
Here is a description on what I want the "remote switch" to do:
When the "remote switch" receives a SMS text "ON", the digital output goes high,  then sends an SMS text "Confirmed ON".
When the "remote switch" receives a SMS text "OFF", the digital output goes low,  then sends an SMS text "Confirmed OFF".
Notes:
I want any phone to operate device and not have to set up "authorized phone numbers"
Cellular signal strength should be able to be checked by sending SMS text "signal" and receive a response (or similar method).

Thanks,
Jim

sdturner

The original Uno footprint is the most common for shields. If you want your shield to attach directly to the Arduino get an Arduino Uno R3. The tasks you describe are not very difficult so any board should be able to handle it. It can be powered from the same 12V as your motor. You will need an interface board or relay card to control the motor. They are also available in the Uno footprint, just make sure the relay shield doesn't use any of the same IO as the GSM shield.

davidrh

I've had good experiences with the Itead 3G shield on both Uno and Mega.  The advantage of the Mega is that it has additional hardware serial ports that you can use with the shield and more memory for processing HTTP responses.

Hansen70

Thanks for the info!
Where can I get a script to make these boards do what I show in my description?
Jim

davidrh

You won't get a sketch to do exactly what you need unless someone is feeling very generous with their time.  Each 3G shield should have a link to the AT command set that drives it.  For the shield that I mentioned, the document is here.

You send the AT commands to the shield over the serial connection.  On an Uno you need to use SoftwareSerial and set the jumpers on the board to the digital I/O pins that you are going to us.  With a Mega, you can patch the Tx and Rx jumper pins to one of the hardware serial Tx and Rx pins on the Mega.

The board I mentioned also has a separate USB port so you can connect it directly to your PC and access it through a terminal program.  This is very handy for working out what the correct AT commands are, as you don't need to code them up into an Arduino sketch or use a serial pass through sketch.

Break your problem down into separate smaller problems and solve them one at a time.  In your case, I think you have at least 4:
  • Send an SMS
  • Receive an SMS
  • Switch a pump on and off
  • Make it as energy efficient as possible


On the energy efficiency front, I ended up switching the 3G board on and off with a MOSFET to save power, as even in software power down it consumed a not insignificant amount of current.  You can worry about this when you have solved the first three items in the list.



Hansen70

 Where is a good source for finding the right person to hire to make my AT command script?

Delta_G

Where is a good source for finding the right person to hire to make my AT command script?
Check the Gigs and Collaborations section.
If at first you don't succeed, up - home - sudo - enter.

Go Up