[amsat-bb] SatPC32 rotor steering via COM1 and G6LVB interface

Jan Lind janlind at mail.dk
Thu Dec 10 11:23:49 PST 2009

Hello SAT-friends.
Has anyone managed to run the rotor steering from SatPC32 via the normal COM1 port.
Setup here: WinXP, SatPC32, G6LVB interface, G-5500 Yaesu rotor and IC-910H.
G6LVB interface programmed and calibrated via COM1 as instructed, all works fine; buttons on G6LVB interface for rotor control works fine, so cabling should be ok.
Starting up SatPC32, SDX starts as well, and Az/El is passed to SDX, as it should, but nothing happens on the G-5500; the same result if Az/El is manually input'ed via SDX.
On a SerialMonitor, all commands looks fine, and correct.
Closes down SatPC32 and starts a TerminalSimulator (Putty) on COM1; types in a command like w100 45, and voila, the rotor acts as it should; command syntax seen on the SerialMonitor matches the commands, sent from SatPC32.
But... there is one difference: RTS on the serial port is low when SatPC32 starts, but high when the TerminalSimulator (Putty) starts; I believe thats the reason commands are not transferred to the rotor (reply >?)
I know in the end, that I have to control the rotor via the FTDI USB interface (virtuel COM-port), but haven't had the time to build it yet, and then CAT-control the IC-910H via the COM1 port; I have tested it, and it works fine (with RTS 12V set in the program).
And what would the situation have been, if I only had 2 COM-ports, and no available USB-port.

If my problem really is, that RTS is low, can I then solve my problem, just by pulling-up the RTS pin, or should I just finish that FTDI USB interface, and forget all about it.

Vy 73 de OZ5JR Jan 
E-mail: oz5jr at mail.dk 

More information about the AMSAT-BB mailing list