Last updated: 27 August 2004
This page is for user comments and information specific to the Meade Autostar Suite. If you have any comments, suggestions, questions or answers to questions posed here, e-mail them to me and I'll post them. Please use an appropriate Subject Line on your message. Thanks. (The Lunar Planetary Imager, LPI, is covered in the Helpful Information - Astrophotography area.)

Subject:	Using IBM Thinkpad with ETX/Autostar
Sent:	Friday, August 27, 2004 13:43:36
From:	Torrey,Kristin (
I have an ETX125EC and an old but serviceable IBM Thinkpad.  The
computer has only a floppy and hard CD-ROM.  It has a serial
port and USB card capability.  I would like to be able to use the
computer with the ETX when I travel to dark sky sites.  I plan to use a
17Ahr Powertank to get all-night power for both scope and computer.  Is
there any way to get the appropriate software into the computer to
control the scope and possibly do some digital photography or use a
Meade LPI as well?

Dark skies & clear nights,

Mike here: There are many ways to get software onto the computer. You can download the Autostar software from Meade's site. You then need a #505 serial cable to connect the computer to the Autostar. For other software that you get on CD-ROM you will have to connect a CD-ROM drive or connect to another computer that has a CD-ROM drive. As to the Autostar Suite, depending upon the speed of the CPU you may or may not be able to use it. Anything less than 500MHz on the PC side is probably dicey. I have used the Autostar Suite on my 1GHz G4 Macintosh (Virtual PC with Windows 2000) and it worked OK.
Sent:	Monday, August 23, 2004 20:23:24
Mike here: If you are referring to the #505 serial cable, see the Helpful Information: Autostar Info page. Also, please read the Email Etiquette page; some advice on the use of ALL CAPS. Thanks.
Subject:	Problem solved
Sent:	Friday, August 13, 2004 05:36:44
From:	Lankreijer-Kroon (
My problems are solved, thanks to your site. The step by step
instructions to set up a communication via the network with a single
computer, did the job.

My previous questions (March and April) were concerning the fact that my
laptop (Windows XP) does not have a serial port, only USB ports. I
assumed that this was the essence of my problem because on a desktop PC
with a serial port (and Windows 98) Autostar suite worked fine. In the
meanwhile I have tried several bridge cables and looked for driver
updates. But now I think it must be something else, because in the
network configuration all works well. I should have tried that a lot

Without your site I never could have solved the problem. Thank you very

Jos Lankreijer
Mike here: There have been reports of some bad cables being included with the Autostar Suite. If you don't have version 3.16a of the Autostar Suite you can download an upgrade from Meade's site.
Subject:	False "Below the horizon" message in Southern Hemisphere
Sent:	Sunday, August 8, 2004 15:09:30
From:	John Lamb (
I am using an Autostar 1 with Version 32E firmware and a Meade ETX90EC.
I am located at Toowoomba, Queensland, Australia.

When the telescope is mounted equatorially, and Autostar Suite tells
Autostar to slew to any object in the southern sky, an error is returned
that the "Object is below the horizon". This occurs even with
circumpolar objects like Rigel Kentaurus which are never below the
horizon at my location.

The autostar will happily slew to such objects using GOTO on the handset
- the problem only occurs with computer control with an equatorial
mount. The problem does not occur in Alt-Az mode. It occurs using both
Autostar Suite and Starry Night Pro, so it seems to be a logic error in
the firmware of the controller. I suspect that it is a Southern
Hemisphere specific problem. All other features work well.

I have emailed Meade, but I wondered whether this was a known problem,
as I couldn't find any other posts about it.

John Lamb
From:	Richard Seymour (
I haven't heard/seen such a complaint on the AutostarSuite groups,
but i'll try to replicate it in a few hours...

good luck
And an update:
Oh, my...

Test Setup: Autostar Suite (i told it i was in Sydney)
ETX90, also set for Sydney.

One-star Align, it chose Rigel Kent.

So i used Autostar Suite's (v3.16a) Object Select to center Rigel Kent,
then i clicked on it, and requested {Slew Telescope]

As John reported, i got a "LX200 Error: 49.1  Object below horizon"

So i fired up PortMon to capture the data going to and from the telescope.
What it sent was the proper: 

:Sr14:39:56#   (autostar returned a "1" for "happy, got that!")
:Sd-60.51:24# (autostar returned a "1" for "happy, got that!")
Autostar returned a "1", which in -this- instance means
"Below Horizon"

To be complete about it, i changed the Autostar to "Alt/Az mount"
and tried again.  No problem, it went.

So -then- i tried telling my Autostar that i really had an LX90.
I had to change the Ratios to match mine.
Set up Polar, did a one-star align (Rigel Kent), (had to unclamp RA since
the LX90 doesn't have a hard stop, it took the short-cut to Sig Oct)
then told StarMap to [Slew Telescope] to Rigel Kent.
**no problems**  It "went"

Oh very my... it's -model- related.   Firmware bug.
That's probably why it hasn't appeared on the AutostarSuite groups,
most imaging folks are using LXD's or LX90's.

I'll look into it (it may be patchable), and have also sent 
 a note to Meade...

thanks for finding and reporting this
have fun
And more:
Oh, that's a fun bug... it's a change they did in v27Go of the code
(yes, the German version... it's not in 26Ed, the last English 
version before the Autostar Suite).  Its first English apparition 
is v3.0Eb, which shipped with AutostarSuite.

So it's gone for a year unnoticed by the general populace?
In part because AutostarSuite wasn't released in the southern hemi
until sometime this year.

The specific coding is "is the target below the lower DEC travel 
of the barrel?"  by the simple expedient of "subtract target DEC 
from lower travel limit setting".  If the result of that is NOT
negative, declare "i can't go there!" and stop.

Peachy.  For positive values of target DEC.

*and* it has a companion bug... by a similar hemi-ignorant test,
it asks "is the Target DEC above my Max Elevation setting?"
But with any negative target DEC, that will never be true.
So you'll never see the "2" of "in the danger zone",
but i think the actual GoTo code prevents damage (i'm checking).

The reason the bug is "model dependent" is that the LX90 can
go to a full -90 in DEC.  So it won't fail the "above horizon" test.

The ETX family has about a -26 degree lower travel limit.

Hmm.. i can simply override the "low limit" test
(i.e. ignore it).. but that may have consequences.
I'll be spending a while tracing the actual GoTo code to see
if it's safe to bypass that test....
I *think* they play belts-and-suspenders, so that the later
chunks of the code won't allow a crunch. 

More later...

have fun
And a fix:
Well, here's the patch... 
if you append the following two lines to the end of my usual patch kit,
or simply apply them (as a text file) as a standalone patch,
or use a hex editor to change bytes x41fa2  and x41fa5 in Build32ea.rom,
they will simply skip the "below lower limit" test at the :MS command.

The tests done at the GoTo section itself -should- prevent 
beyond-limits damage to the scope, but they won't tell AutostarSuite
the "1" it should hear to tell you that it couldn't make it.

I see that the "below horizon" doesn't care about east/west 
("not risen yet","already set" concerns.  It depends upon the
StarryNight/AutostarSuite/whatever to not ask for such silly things)

R 41fa2   2f  20
R 41fa5   31  40

have fun

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