I'm using a breakout port for the JTAG connection, a SUBD-15 with a
protective screw-on port cover. The female end is at the housing.

This way, I can reprogram the CT800 without opening the housing. The port
cover is important since otherwise, ESD sensitive CPU pins would be
exposed to accidental touch.

The total cable length of the 20 pin ribbon cable must not exceed
20cm, or else the JTAG connection may not work properly. Shorter is
better, of course.


JTAG     SUBD-15
1          1
2          2
3          3
5          4
7          5
9          6
11         7
13         8
4/6        9
8/10      10
12/14     11
15        12
17        13
16/18/20  14
19        15