Wireless Recycled Reef Controller

Bill of Materials:

Note, Maxim offers Free Samples of their most Chips. Just sign up on Maxim's Site put together your Samples List and they ship them to you for free. {insert ethical ramblings of not abusing the system here}

Desoldering Wick
http://store.yahoo.com/webtronics/2mmsowiz.html

Here is the assembly diagram for mounting the parts on the above board. The boards image is reversed because you're looking at the board with the copper traces down, and the top (without copper) is the component side.



The actual schematics from the datasheet
http://pdfserv.maxim-ic.com/en/ds/MAX220-MAX249.pdf



Now to add header strips. This is optional, you can hard wire direct to the router and to a DB9 connector if you wanted. I needed something flexible so I can move wires around.





Powering the board
http://www.fairchildsemi.com/ds/LM/LM7805.pdf


How to use this board.

The way I built it, I can take regulated 5 Volts from the board via the 2 pin header.

The long header strip:

1 | 2 | 3 | 4 | 5 | 6 | 7 | 8

Header to MAX232 Pinout

1 goes to pin 9 of the MAX232
2 goes to pin 10 of the MAX232
3 goes to pin 11 of the MAX232
4 goes to pin 12 of the MAX232
5 goes to pin 13 of the MAX232
6 goes to pin 14 of the MAX232
7 goes to pin 7 of the MAX232 (remember we cut the trace and added a jumper)
8 goes to pin 8 of the MAX232 (remember we cut the trace and added a jumper)

Header Pins:
1
2
3 goes to TTL pin 4 of router this is ttyS0
4 goes to TTL pin 6 of router this is ttyS0
5 goes to RS232 DB9 Pin 3 (Transmit Data of a PC)
6 goes to RS232 DB9 Pin 2 (Receive Data of a PC)
7
8

Grounds need to be connected on both router and PC. So from the PC's DB9 pin 5, connect that to the Ground bus of the board.
Pin 10 of the router to another Ground pin.

When I say the ground bus of the board, if you look at the 2 Pin header we use for regulated 5 volt power supply. The thick negative trace (the lower one), anywhere along there is the Negative Ground bus.

Tearing apart the WRT54G
Now you'll have to disassemble your WRT54G. See below for a pictorial from Paul Whitby.

Installing the header strips on the WRT54G takes some work. If you have a good solder sucker, that will probably be the easiest way to open up the holes again. Then clean it up with desoldering wick.

I used desoldering wick, you have to desolder as much as possible on both sides of the board. The 2 ground pins (9 and 10) took the most
work because it is on a large ground plane. Turn up the heat on the soldering iron if you can.

Or you can try using pogo pins to "plunge" on the contacts.
Other Ways
Rod Whitby's Method. Includes disassembly instructions. He uses the Max233, so no external power is needed. This of course won't help you power the DS2480b? or provide power to devices that steal power from the port such as the X10 Firecracker.
http://www.rwhitby.net/wrt54gs/serial.html