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Never did get a picture of this project running

The idea is that an SMS phone can be used to receive SMS messages that can then be displayed on a large format message board.

Hardware	Description
	Atmel AVR Microcontroller Development System This kit was kindly provided to me by the friendly people over at http://www.btinternet.com/~e2one/avrbrd/
	8×24 LCD Display Details of how to wire up a 8×24 display to the development board can be found at http://www.btinternet.com/~e2one/avrbrd/ (see the 8×24 LCD Project). If you use a smaller display then you will have to modifying the code to suit.
	A mobile phone I used a NOKIA 7110 but any phone that has a built in modem should be ok.
	A DLR-3 cable A phone connector wired to a DB9-F. If you don't have one or you can't afford to buy it then there are some good solutions for making your own

As the ATMEL AT90S2313 only has 2k of code space the demo version of BASCOM can be used without hitting any of its restrictions.
Hyperterminal or any suitable terminal emulation package. Useful for making sure that your GPS unit is tranmitting data.

A great site for the wiring of all things RS232 can found at http://www.lammertbies.nl/comm/cable/RS-232.html

9 Pin Connector on a DTE device (Phone connection)

Pin Number	Direction of signal:
1	Carrier Detect (CD) (from DCE) Incoming signal from a modem
2	Received Data (RD) Incoming Data from a DCE
3	Transmitted Data (TD) Outgoing Data to a DCE
4	Data Terminal Ready (DTR) Outgoing handshaking signal
5	Signal Ground Common reference voltage
6	Data Set Ready (DSR) Incoming handshaking signal
7	Request To Send (RTS) Outgoing flow control signal
8	Clear To Send (CTS) Incoming flow control signal
9	Ring Indicator (RI) (from DCE) Incoming signal from a modem

Nokia 7110 DLR-3

Pin	Signal	Specs
1	V In	0..8.5V, 0..850mA
2	Chrg Control	PWM, 32..37 Hz, 1..99%
3	XMic / Device Selector
4	SGnd / DLR-3 VCC	3.3 V
5	XEar / DLR-3 RTS
6	MBus	9600bps
7	FBus Rx / Modem	9600 - 230.400 bps < 0.8V : '0' > 2.0V : '1'
8	FBus Tx / Modem	9600 - 230.400 bps < 0.8V : '0' @ max. 4mA > 1.7V : '1' @ max. 4mA
9	LGnd

The standard cable that is supplied with the AVR development kit uses a 3 pin configuration for RS232 data. It is wired as a DTE with built in loop back handshaking.

AVR RS232 DB9 wiring The DLR-3 cable expects partial handshaking from a DCE. The problem is the AVR board does not implement any hardware handshaking and is wired as a DTE.

To overcome this problem we will build a new cable. This will be wired so that the AVR board is seen as DCE, additionally it will also have a hardwired active DTR signal.