Hi,
Does it exist small embedded programmable controllers using basic or something which can be connected to a cellular phone and be able to decode SMS messages sent to this phone?
According to the SMS sent, the controller should be able to compose and send a new SMS message according to voltages read from AD inputs or levels read from digital inputs.
Thanks a lot for comments + hints and info about such devices.
regards
Geir
Are you doing this for production or hobby? If hobby get yourself an old-ish 2001-2004 model Siemens handphone. Almost all of them have a built-in, TTL level, RS232 port which is easy to interface to any microcontroller. The protocol used to communicate is the classic modem AT/OK protocol but extended to support SMS (documentation can easily be googled). So to find the baud rate simply test with hyperterminal by sending out "AT" and keep changing the baud rate until you get an "OK" reply.
To interface with the phone get a Siemens RS232 data dock for the more expensive models. The cheaper phones don't have data docks but trust me, they work on them too. Alternatively build one yourself using a
3.3V RS232 chip.If you are doing this for production then Nokia has some GSM modems which are good but quite expensive. Most handphone/GSM/SMS modems use similar protocols.
On Fri, 3 Mar 2006 18:15:44 +0100, "Geir Holmavatn" put finger to keyboard and composed:
Silicon Chip had a kit that made use of old Nokia phones:
Unfortunately the article is pay-for-view.
- Franc Zabkar
These are Nikia phone in Europe.
The Nokia phones in the US will not work like these.
Donald
There's a device that has the same functions as a cellular phone, but doesn=B4t have a screen. It=B4s clasified like a GSM modem, but i think it=B4s better. Basically it's a Java programable mc, with A/D channels, digital inputs.... Your java IMLET can have GPRS, SMS, MMS... management. Look for Aplicom 12-12i on google.
It is more a 3.3 volt like level. Sending 5 volts into the signal line will detune it or whatever and it loses network.
The S35/M35 do this. And should be free by now.
I think there is even a way to turn the thing on; at least there were cables that helped you flashing the phone by somehow 'pressing the ON button' for a short moment.
Inded that's it.
Thomas
This might be useful for you:
Geir Holmavatn wrote:
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