Arduino text‘in.
Key Features:
24 relays controlled by 4 I/O lines!
Cell phone text using your Arduino.
This project hacks a cell phone to text using normally open relays. After investigating cellular modules on the internet I decided it looks not only rather pricy, but also like a possibility that even after I had it working that a cellular provider might not let me put the device on their network. It seemed like a good cell phone hack was in order to make this work for me.
Key Features:
24 relays controlled by 4 I/O lines!
Cell phone text using your Arduino.
This project hacks a cell phone to text using normally open relays. After investigating cellular modules on the internet I decided it looks not only rather pricy, but also like a possibility that even after I had it working that a cellular provider might not let me put the device on their network. It seemed like a good cell phone hack was in order to make this work for me.
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Signing UpStep 1:
Purchase a cheap prepaid flip phone, activate and charge it. Mine was $20.00.
Flip phones are fairly easy to disassemble. You will need a very small screw driver set. The button pads on the inside are still large enough to allow for soldering wires in place without too much trouble. The prepaid plans let you text for pretty cheap too if you pick the right plan. Plus because its prepaid you can just let it run out whenever you are finished with it and best of all no contract.
Turn on the flip phone and take some notes about how it operates. Yours may access menus and things differently then mine does and its nice to know as you move forward with this.
Figure out what keys you still want to have access to once the phone is mounted. Because I used a prepaid phone I have to access it now and then to add more air time. It is also helpful to know how things are going with the phone when you can turn it on and activate it with the buttons after it is mounted to the board. The buttons on your cell phone board will be connecting directly to the phone. This way you can access the phone even if the rest of the circuit is off or maybe just doing other things.
Safety First. Remove the battery from the phone. Tear apart the flip phone. The circuit board inside is pretty delicate and has some sharp parts so use some caution. Do not break the LCD displays and be very careful not to destroy the very small ribbon cables that interconnect things. The part of the phone that houses the LCD, microphone and usually the camera will need to be taken completely out of the case. The flip phone I purchased had enough room to flip the camera around so that it can still take pictures. The case for the main board of the phone (where the battery is) will need to stay more or less intact. This makes it easier to put the battery back in and your not messing with the built in antenna so it should still have its normal signal strength.
Flip phones are fairly easy to disassemble. You will need a very small screw driver set. The button pads on the inside are still large enough to allow for soldering wires in place without too much trouble. The prepaid plans let you text for pretty cheap too if you pick the right plan. Plus because its prepaid you can just let it run out whenever you are finished with it and best of all no contract.
Turn on the flip phone and take some notes about how it operates. Yours may access menus and things differently then mine does and its nice to know as you move forward with this.
Figure out what keys you still want to have access to once the phone is mounted. Because I used a prepaid phone I have to access it now and then to add more air time. It is also helpful to know how things are going with the phone when you can turn it on and activate it with the buttons after it is mounted to the board. The buttons on your cell phone board will be connecting directly to the phone. This way you can access the phone even if the rest of the circuit is off or maybe just doing other things.
Safety First. Remove the battery from the phone. Tear apart the flip phone. The circuit board inside is pretty delicate and has some sharp parts so use some caution. Do not break the LCD displays and be very careful not to destroy the very small ribbon cables that interconnect things. The part of the phone that houses the LCD, microphone and usually the camera will need to be taken completely out of the case. The flip phone I purchased had enough room to flip the camera around so that it can still take pictures. The case for the main board of the phone (where the battery is) will need to stay more or less intact. This makes it easier to put the battery back in and your not messing with the built in antenna so it should still have its normal signal strength.
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This same technique also works with lcd displays. Shift registers are amazing :)
I will see what I can do about a video. I agree with you about the sound of relays. I used reed relays in this so they are really quiet. I did turn the sound on for the button activation on the phone and that is still very satisfying.
do the instructables gave you the pro membership as a gift for this great instructable?? cause i got for three months a promembership gift for my which is How to make a soldering iron with a 6 volts battery you can search it's featured!
do the instructables gave you the pro membership as a gift for this great instructable?? cause i got for three months a promembership gift for my which is How to make a soldering iron with a 6 volts battery you can search it's featured!
Your instructable "How to make a soldering iron with a 6 volt battery" is very creative. I am amazed every day at how creative people can be. It had never occurred to me before looking at your project to try to make my own solder iron. Thank you for sharing your talent.
Build_it_Bob
You can get 25 for $4... probably less than 2 relays. You are already using a transistor to drive a relay... see if you can drive the switch directly.
If that doesn't work you can look at something like this...
http://www.digikey.com/product-detail/en/CPC1972G/CLA224-ND/1025050
Then you won't need the transistor and relay... the device will do both making your circuit simpler. Here is the datasheet
http://www.clare.com/home/pdfs.nsf/0/E16FD7FE1462A2DD852570F800586DFD/$file/CPC1972.pdf
Just need a dropping resistor for the input... but that's pretty simple.
Jerry
http://www.instructables.com/id/Samsung-MOD-fixed-...-mobile-...-TV/
You may be able to simplify your circuitry a lot. The keypad probably uses the ever-common "pull high, connect to ground" model of switches (that is, one side of each button is tied to an input pin somewhere and a high resistance pulls it to +V and the other side is connected to ground so when the button is pushed, the input sees 0V, otherwise +V.) If that's the case, you can then go with one wire to each button pad and one wire to a common ground. Also, since your phone is isolated from your Arduino, you can then just use an NPN transistor with the collector connected to the button pad and the emitter to the common ground which you'd then tie to the Arduino's ground. The transistor driver for the relay can then be used without the relay. I hope that's clear enough!
http://www.instructables.com/id/The-S45-SMS-Alarming-System/
I am not shure how this works with Samsung phones. But I belive that it is possible, ate least using properitary AT codes of the manufacturer.
http://www.falcom.de/uploads/media/a2dman.pdf
Maybe theses AT-commands work for other devices too ...
I, for instance, use TracFone, and get charged for every single message I send or receive. Though I do still have an older phone that gave me free messaging.
What would be REALLY neat would be if you could mount it all in a case small enough to fit in your pocket!
What would be the ultimate in cool is if you could still use it for sending and receiving calls. Then you wouldn't be forced to carry two phones, one for texting, and one for calls.
http://www.seeedstudio.com/depot/gprs-shield-p-779.html?cPath=132_134
with an Arduino.
The relays are controlled by the Arduino that is running the program. The Arduino doesn't actually monitor the buttons. The buttons are there so you may interface to the phone should you need to.
Thank you for the question.