i.e. : http://romain.novalan.fr/wiki/Flash_Fonera_2100_with_OpenWrt_by_console_port_and_redboot
We have already done parallel breakout cables. (http://www.instructables.com/id/No-solder-parallel-port-break-out/) and I have eluded to a joystick port break out cable. Now I would like to do a serial port cable. Why? I have been finding more and more aricles about interfacing to the serial port. Everything from temperature sensors, radio transmitters, and even used just for power. You could also use with with the appropriate electronic parts to be a jtag cable.
Notice: Try this at your own risk. I will not be responsible for any issues. If you are unsure, get a professional to help.
Note: bc547=nte123ap bc557=nte159
Step 1: All serial voltages are not the same.
With all kinds of usb interfaces about, it seems like there is a usb for everything. With the increase in the need to attach to micro-controllers routers and other flashable hardware, it does not hurt to get to know the rs323 port. Pinout's are usually documented. You have to be careful though, because you have to know what voltage you are working with. 12, 5, and or 3.3. Maxim and other companies make special chips to make this easier. Epanorama.net has some good information also.