As a supplement to the things on this subject already posted...
This thread will cover how I am hooking up my own cable.
First, the cable doc sheet (FTDI Chip adapter cable):
The Kindle uses the 1.8 volt (1V8) model cable.
Second, the chip doc sheet for the chip inside the cable:
Gives a full description of the tricks the USB-serial chip can do.
Windows, Linux, Mac OSx all have drivers for this cable.
Some may also support the "bit banging" interface to the chip.
For those who want to read ahead...
This is how I did it for one of my media players:
Only the physical details (and voltage of the cable) will differ on the Kindle.
The prior thread on this subject here seems to have died off a couple of years ago:
Which gives me a chance to re-invent a way of my own.
The information available on Linux about the adapter cable and its drivers is down here:
The cover light connector and pads reported in the original thread as the serial port connections on the Kindle3 (here, a 3g, Keyboard model) is down here:
The pad signal assignments are found in this post:
The internal details of the J14 socket here:
A dimensioned sketch of the internal contacts here (as a png image):
The cad file of the sketch (as dxf):