[Barrykgerdes]

The EQ series of mounts when fitted with a Synscan controller can be controlled directly through a serial port by Stellarium.

Stellarium at the moment has two generic control protocols, the Meade and the Celestron Nextstar.

The control by Stellarium is only rudimentary in so far as it can read the telescope position coords and write a set of coords to the telescope and then execute a "goto"

Direct control of an EQ mount can be executed via a contoller refered to as the EQMOD that directly controls the stepper motors, bypassing the Synscan. Stellarium can only control this drive via the third party interface ASCOM. ASCOM then has an interface to the EQMOD.

The Meade controller has quite an extensive range of commands that can be accessed by a computer.

The Argo Navis responds to a sub set of these commands and has a set of its own.

The Gemini uses a comprehensive subset of these commands an a suite of its own.

Celestron has a much smaller range of commands that can be accessed by computer but adequate for most users who write their own software.

These additional commands are utilised by some third party programs interfaced with ASCOM.

The Synscan uses a very basic subset of the Celestron protocol and can only read the coords and a send a set of coords with a goto.

I have been experimenting with computer control of the Synscan and some extra commands can in fact be executed synthetically. Also the latest version of Synscan has an undocumented feature in the utilities menu called PC Direct Mode. This feature allows ASCOM and EQMOD to drive the mount without the special hardware interface cable.

Barry