Wifi-bot: Router-Arduino interface

I hope this is the right spot to ask this question.

I would like to build a WiFi bot similar to this one:
http://www.jbprojects.net/projects/wifirobot/

The WRT54 router is known for its 'hidden' serial port inside. Most tutorials use an RS232 adapter and a DB9 connector to interface with it.

But since my arduino has no DB9 connector, but the newer USB instead, I was wondering if I could use this 'FTDI-to-USB' adapter from Sparkfun instead.

Any information would be greatly appreciated.
Thanks in advance.

Why not just get an ethernet shield for the arduino and skip hacking the router? With the ethernet shield you would connect to the router with a cat5 patch cable.

Because the arduino ethernet shield costs 45 dollars + 20 dollars or so for shipping.

No you cannot use a FTDI usb-serial cable or adapter to connect an Arduino to the WRT, they are both devices. The USB end of the FTDI requires a USB Host or host controller (PC), not a device. But, I believe the RS-232 voltages are either 5V or 3.3V for the WRT which means you can open it up and run 3 wires (TX,RX,Grnd) and connect it directly to your Arduino serial port rather than using a DB9 connector. There are also these and others if you don't want to open up the WRT: http://asynclabs.com/store?page=shop.product_details&flypage=flypage.tpl&product_id=24&category_id=11&vmcchk=1.

I believe the RS-232 voltages are either 5V or 3.3V for the WRT

They are 3.3V

(...)connect it directly to your Arduino serial port.

Do you mean right into the Tx and Rx (pins 0 and 1 and Gnd) of the Arduino? Because I thought my Arduino serial port was the mini USB connector on it?

Skullforger

I sent you a PM. I don't know how to do this but I too am trying the exact same thing with the exact same project ... lol.

HerrBall

Can someone tell me what ceke means by this:

I believe the RS-232 voltages are either 5V or 3.3V for the WRT which means you can open it up and run 3 wires (TX,RX,Grnd) and connect it directly to your Arduino serial port rather than using a DB9 connector.

I looked it up and the WRT router does use 3.3/GND for its serial line voltage levels.

The thing I can't find out is where on the Arduino I have to connect the TX and RX wires? Do I have to use the Digital Input pins for it and then use the Software Serial like in this tutorial? http://www.arduino.cc/en/Tutorial/SoftwareSerial

On my Arduino, the hardware serial port is a USB port, so I cannot just run 3 wires to that.

The thing I can't find out is where on the Arduino I have to connect the TX and RX wires?

On my arduino over on a corner are pins 0 and 1, which are marked tx and rx. On my board these work with TTL rs232 communications.

On my Arduino, the hardware serial port is a USB port, so I cannot just run 3 wires to that.

On your Arduino - the hardware serial port is, well, a hardware serial port. The USB is simply a USB to serial adaptor. If you squint at your board really close you see the two pins marked Tx and Rx.