Last updated: 14 March 2005

Autostar Suite Protocol Description

Sent:	Wednesday, March 9, 2005 13:17:21
From:	Mark Ewert (
Meade produces a software package called Autostar Suite which includes a
planetarium program along with telescope and dome control software. The
telescope and dome control software allow the user to control the
telescope and dome remotely over a network. To control the dome, the
user manual states that the use must have a dome controller. I wanted to
use the Autostar Suite to control my observatory and my telescope
remotely so I contacted Meade to purchase the dome controller but was
told that Meade is not going to produce the dome controller. Meade's web
site at this URL: continues
to market this feature although it is not available.

I thought that I could build a dome controller myself if I could get the
software protocol. Meade has published its telescope control protocol so
I thought that they would be willing to provide the details of the dome
and `netscope' protocols. Meade declined stating that the protocols are
proprietary. A simple network sniffer is all that is needed to examine
the protocol and reveal the communication interface.

Here is the information that Meade doesn't want you to know:

Telescope Control
Netscope.exe is the program that translates the network commands into
serial port commands to the telescope and vice-versa. The protocol is
very simple (thankfully). The protocol has two main phases which I call
the Setup phase and the Normal phase.

The Setup phase is first activated when netscope detects a new
connection request. Netscope sends a password request and the remote
user responds with a password. If the password is correct Netscope
replies with "OK" and enters the Normal phase. If the password is not
correct Netscope dissolves the connection and returns to listening for
new connection requests. This is shown below.

Remote PC Netscope COMM Telescope
.         < PSW?
`pasword' >
.         < OK

The Normal phase is made up of a routine handshake sequence and
telescope protocol commands. The routine handshake sequence is initiated
by the remote PC with the transmission of ":LK0#" followed by the
transmission of ":LK1#". The proper response by netscope is "Yes#".
Failure to properly respond to these handshake requests results in the
Autostar Suite displaying a connection failure message. The Handshaking
Sequence routinely occurs throughout the Normal phase. The protocol is
shown below.

Remote PC Netscope COMM Telescope
:LK0# >
:LK1# >
.     < Yes#

The Normal phase is otherwise composed of telescope protocol commands
and their responses. The telescope protocol is documented in the
telescope protocols published by Meade. Here is a link to the latest
protocol definition:

The protocol includes the following command set commands:
`.' ACK Used to determine the telescope axis alignment, ie. Polar or Alt-Az
:U# Used to toggle between low and high precision
:GD# Used to get Declination Coordinates
:GR# Used to get Right Ascension Coordinates
:Srxx:xx:xx# Used to Set right ascension coordinates
:Sdxx:xx:xx# Used to Set declination coordinates
:Q# Used to Stop all motors
:RS# Used to set the motor rate to Slew rate (Fastest).
:RM# Used to set the motor rate to Find rate (Second Fastest).
:RC# Used to set the motor rate to Centering rate (Second Slowest).
:RG# Used to set the motor rate to Guide rate (Slowest).
:FQ# Used to stop the focus motor
:FF# Used to set focus motor rate to Fast.
:FS# Used to set focus motor rate to Slow.
:F+# Used to move focus motor in.
:F-# Used to move focus motor out.

The responses are as provided by the telescope over the serial line.
Here is an example:

Remote PC Netscope COMM Telescope
:GD# >
.                  :GD# >
.                       < -26:34:00#
.    <-26:34:00#

For all of the telescope commands, netscope acts as a relay agent taking
the commands from the network and providing them to the serial port.
Likewise the replies from the telescope are read from the serial port
and are returned to the network.

Potential Netscope Security Problem
I've previously reported on the network and to Meade that Netscope has a
potential security problem in that when the user tells netscope to open
a port Netscope actually opens the port the user identified as well as
the following 4 network ports. These additional ports are not mentioned
in the user guides. When the user tells netscope to listen to the
primary port, all five ports are opened in listening mode. If the user
deselects the listen checkbox, only the primary port is closed and the
other four ports are left open in listening mode. If a remote user tries
to connect to these ports, the primary port is reopened for listening
mode and functions as normal, however, the user's screen continues to
show the port listen mode as disabled, although the status line is
updated to indicate commands are being executed. A user might mistakenly
think that they've taken their scope off the internet by deselecting the
listen checkbox; however, the netscope design can still allow the remote
user to move the scope. In my situation this can have disastrous effects
as the scope could be driven into the ceiling of the roll-off roof when
the roof is rolled on.

Dome Control
The Netscope.exe program has a window for identifying the COMM port to
which the dome controller is connected. NETSCOPE makes no attempt to
actually acquire this COMM port. The Dome control features appear to be
a complete faade.

The Autostar suite running on the Remote PC offer the operator a window
with buttons marked Open Shutter, Close Shutter, Track to Scope, etc,
however, the remote PC makes no attempt to actually make a network
connection to the address and port the user provides. The program
appears to be simply a graphical window which actually does nothing.

Since Meade claims all of this functionality works in their
advertisements on the web (See and my investigation seems
to indicate that it can't possibly function, some people might conclude
that Meade is guilty of lying or even false advertising. Others would
call this `Creative Marketing'. It's no wonder Meade didn't want to
divulge the Dome control protocol seeing that there isn't any!

I've sent Meade an Email and a FAX describing the NETSCOPE port problem
but they haven't returned my messages. I plan to produce Microsoft
Visual Basic programs that replace the netscope.exe and the dome control
programs in Autostar Suite with versions that actually work in the near
future  providing there is community interest. I also want to produce a
netscope version that controls a Celestron CGE mount instead of only
supporting the Meade Telescopes, but again, only if there is community



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Copyright ©2005 Michael L. Weasner /
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