cable for nexstar 6se firmware upgrade

[veejo]

I'm trying to upgrade the firmware on my nextstar 6se.

I believe this is done by plugging in a 4p4c cable into the handset, and the other end into an db9 rs232, which I have on my PC (real one, not usb convertor).

I've tried to make up one cable from a picture on the internet, uses 3 wires of the 4 tx, rx, gnd i pressume, but no response, just times out (wrong pins on cable or DB9 ??).

Does somebody have the pinouts or a pdf of one they made and knows to work ?

Do I need a null modem ?

can I flash both the base and the handset from the same port on the handset ?

There is an aux port and guide port on the base. Current firmware is a version 4.xx but not latest

[MikeyB]

See if one of these helps.

[veejo]

Mikey

thanks for the info BUT the cable in the pdf is an 8 pin rj45 8p8c, but as per the wiring diagram, I need the cable to program the hand controller, the cable that goes into the bottom of the controller is 4p4c,

[MikeyB]

Hmm - in that case, this should be what you need: Hand control RS232 port cable (http://www.nexstarsite.com/PCControl/RS232Cable.htm)

[mithrandir]

The easiest place to get the 4 pin plug is a replacement telephone handpiece to phone cable. I got a coiled one and it works fine. You can either make up an RJ11 socket to DB9 cable to plug the other end into, or cut the other plug off and attach the DB9 plug.