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Last updated: 27 August 2010
This page is for user comments on Astronomy software for the Windows (including the Meade AutoStar Suite), Macintosh, or Palm OS systems. Items that are more "review" oriented will be posted on the Astronomy Software Reviews page. If you have any comments, suggestions, questions or answers to questions posed here, e-mail them to me for posting. Please use an appropriate Subject Line on your message per the Site Email Etiquette. Thanks. Remember, tips described on this site may invalidate the warranty on your telescope or accessories. Neither the submitter nor myself are responsible for any damage caused by using any contributed tips.

Subject:	Help Please
Sent:	Thursday, August 26, 2010 09:14:24
From: (
I have a etx90. I can not get my laptop to do anything with the scope.
The scope works fine by itself but the computer will do nothing but give
me error messages about ports. I am using a compaq laptop running XP. I
have a Belkin serial adaptor into the USB with all drivers installed
properly. It is using com port 6 but I have entered it and it times out.
Also the LPI wont work either.

I have tried several things suggested on your site but nothing works. I
have even tried "Coolterm" from your site, but that does nothing either.

I guess its because I am not great at computers and need detailed step
by step instructions.

Please Help if you can.
Kevin W
Mike here: Hey, it is your lucky day. I accidently saw your message as it was being deleted UNREAD as SPAM due to the ambiguous Subject line. As requested on the ETX Site home page, PLEASE read the Submittal Guidelines. Thanks for understanding.
As noted many times on the ETX Site, not all USB-serial adapters work with the AutoStar. See the article "AutoStar and USB" on the Helpful Information: AutoStar Info page. However, I need more information before I can provide further suggestions. What application are you using to try to communicate with the telescope? If using the AutoStar Suite, have you enabled the network protocol?


Thanks for catching my e-mail. I am using the autostar suite. I have no
idea what network protocol even is so I would think not. I also just
went and bought a new usb connector. I tried to fond the one you use but
its not available in my area so I bought a Dynex to try that.
Mike here: See the articles "AutoStar Suite on a Macintosh" (which discusses the network protocol) and "Network Server Capability" on the Helpful Information: AutoStar Info page. In order to use all of the applications that make up the AutoStar Suite, you need to enable the network protocol. You might also try some other application, like ScopeDriver or Astroplanner, to see if they can communicate via your USB-serial adapter.



I got it. Thank You.

Just to show you what a complete idiot I am, I had the cord plugged into
the aux port of the scope and not the hand control.

Ill try to get this down, it just might take me a few years of fooling
around with it.

Your site is GREAT
Thanks again
Mike here: Yep, got to use the right port! Glad you solved it!
Subject:	re: usb cable 505
Sent:	Friday, August 20, 2010 20:58:48
From:	richard seymour (
I just saw your posting to Mike Weasner's site.

To answer your first question: NO!  IT WILL NOT WORK to simply attach a
USB-shaped plug onto a 505 cable.

The voltages and signals in the Autostar's RS232 serial socket are
**completely different** than the voltages and signals in your PC's USB

For example, the rs232 socket has a pin that is bouncing between plus
and minus 12 volts. Your PC's USB socket expects to see signals that go
between zero and +3 volts.

Thus the Autostar's voltages could seriously damage your PC's USB socket
drivers. (just for starters).

Next, we look at the "protocol"... that's the way the signals are
interpreted. For the rs232 serial connection, they are sent at (for
example) 9600 baud. That means the signal goes from negative to positive
and back about 9600 times per second. And -all- that's there is the raw

USB signals move much much faster... up to 12 megabits per second for
USB 2.0 And it's a multi-device "bus", so the data is preceded by
address bytes, header information and checksum data.  The actual "data"
is buried under a pile of "overhead".

So really: your idea of a USB socket directly connecting to any of the
Autostar's sockets simply WILL NOT WORK. (and may damage expensive

To communicate between your PC and the Autostar, purchase (either)
Meade's USB to serial adapter AND a 505 cable, or perhaps a Keyspan
USA-19HS and a 505 cable.

good luck
Mike here: Thanks for expanding on my responses. Good to know that nothing changed in the USB-serial communications technology when I wasn't looking.
Subject:	usb cable 505
Sent:	Monday, August 16, 2010 13:11:05
From:	MARION (
I was looking at your instructions on building a 505 cable using an
rs232 plug, Can I use a usb plug instead?  pins on usb= 2 d-, 3d+, 4
gnd, on usb 4 would still hook up to pin 4, 3 to 1, 2 to 2, what do you
think, sorry to bother you so much, I called meade and they said to
trash my scopes and buy new ones.  Really, so I will ask you questions
until you get tired of answering them.
Mike here: Well, you COULD use a USB plug. However, you would still need some electronics and software to convert from the RS-232 protocol to the USB protocol.


I will let you know if it works.
Mike here: Looking forward to hearing how your software and electronics development goes. The cable is the easy part.


I found the software at meade to use the usb port, here is the link

thanks for your help
Mike here: Yep. Now you just need the Meade USB-Serial adapter cable that uses their software.


The process I am heading into will not work?  From reading meades page
and checking the pins on each port, I thought it might work.  If you
know this won't work, I would appriciate the insight so I might not
destroy some hardware. when I come by your part of the country this fall
or winter, will drop you off a case of your favorite beer, water or
Mike here: As I said earlier, you "still need some electronics and software to convert from the RS-232 protocol to the USB protocol". It is not just a wiring problem. For more on USB adapters, see the article "AutoStar and USB" on the Helpful Information: AutoStar Info page. Not all adapters work reliably with the AutoStar. I recommend Keyspan.


I just finished talking to meade tech support, the usb software was
written for the new meades, they do not know if the download process
will work on the older models like I have.  He told me to try it and if
it worked to let him know.  Do you know anyone who has made a cable
using a usb plug and tried to download onto the older computers?  If
not, I will fix a cable and try.
Mike here: You are not understanding what I'm trying to tell you. More than a pin-to-pin wiring change is required when going from a USB port on a computer to a RS-232 device (like the AutoStar). Three things are required: the cable (which does the pin conversions), electronics that handles the signals in the wires, and software to tell the computer that is talking with the USB protocol how to send/receive the RS-232 serial commands.


Yes, I understand that, and that is what i talked to meade tech support
about.  they have not tried to download software on the older scopes
using their usb driver software.  he told me if i tried it, let him know
if it works so he can pass the info on.  I thought maybe they had tried
it but, he said they just kept up with the new scopes.
Mike here: If you have the Meade hardware adapter and software, it should work with all their RS-232 handcontrollers. I don't know that from experience since their software is limited to Windows only. But I'm sure it has been mentioned as working with ETX models.


I am going to order a 505 cable and wait until it is here, then do the
downloads,  I think it would be best for me, will add a lot less to the
learning curve for me.
Mike here: Just remember that the #505 serial cable connects between the AutoStar #497 and a RS-232 on the computer. If your computer doesn't have a RS-232 port, you will need a USB-serial adapter.

And more:

I made the cable last night and it didn't work with their software. 
Called meade this morning and the tech said what I made would not work
on my 64 bit computer but will work on a 32 bit computer.  They are
devleoping the usb driver software now for a 64 bit computer.  I
explained how I wired the usb connector an hand connector, he said it
was wired correct and would work on 32 bit computers now.
Mike here: Just to confirm, you DO HAVE the Meade USB-Serial adapter cable, not just the #505 serial cable you made? As I've been saying, you can't just put a USB connector at the end of the #505 serial cable and expect it to work. You need an adapter with electronics and software.


No, its the one I made.  I explained to the man at meade how I made it. 
He said it would work with the new software for 64 bit.
Mike here: So, what "chip" did you use in the cable you made? The software (from Meade or elsewhere) is dependent on the chip design. That's part of the electronics I've been mentioning.


I talked to the older man at meade tech support.  I explained I wired
the usb connector like it was a regular rs232 connector.  He said it
would work as wired with the new 64 bit software when it was completed,
I don't understand how it will work without using  the 5volt line to
activate the usb plug and play mode.  Will see when it is published.  As
it is right now, I can not install any downloads to my scopes until the
64 bit drive comes out.
Mike here: I have my doubts about that working. But maybe it will. I've never written any device driver level code.
Subject:	Trouble connecting ETX 80 with Autostar software
Sent:	Tuesday, August 10, 2010 02:21:23
From:	Paul Randall (
I have a meade ETX 80 with auto star # 494 controller. The current
firmware on the controller is 13Ed, although I learnt recently this
cannot be upgraded on this controller. I have the correct connector kit
# 506 with a serial port to usb adapter. I have installed the latest
driver for this and the latest Autostar software from

The issue I have is that I cannot get my ETX 80 to work properly with
the software. I can control the telescope from the LPI program in as
much as I can make it move up down, left and right but I cannot connect
the telescope by going to telescope>protocol>Autostar via serial port
(F6) and therefore use the other funtions in the Autostar suite. When I
do the above I get the following error message "Error -1 Can't open
COM10 : Getlasterror returned 2".

I have attached a sceen shot of the error message.

I hope that I have included all the necessary details and I would realy
apreciate any help you cuold give me!
Paul Randall


Mike here: Have you enabled the Network Protocol in the AutoStar Suite? You need to do that to have the muitiple AutoStar Suite apps control the telescope via the single serial port connection. For more on the Network Server, see the "AutoStar Suite" section on the Helpful Information: AutoStar Info page.
Subject:	Meade ETX-70ATAstroTelescope with Autostar
Sent:	Friday, August 6, 2010 10:22:58
From:	Peter Lloyd (
I purchased my Meade ETX-70ATAstroTelescope with Autostar in June 2002 .
The invoice says

"MEADE ETX-70AT 2.8mm/350mm ASTRO w/ AC". 

I have controlled  the Telescope with the AUTOSTAR  since purchase  and
now want  to control  it from a MS Windows  PC. I anticipated that
future want  in 2002 and purchased "Meade 506 ASTROFINDER software with 
CONN KIT but did not try it. However it is clear from your website  that
I should get more up-to-date software. I want to start with something
simple could you please make a suggestion. For example, I would like to
specify the viewing direction and have my telescope goto to them
Mike here: Check out Scopedriver or AstroPlanner. See the Accessory Reviews: Software page for more info on them. There are many "planetarium" apps that will control the AutoStar telescopes.
Subject:	Android Software question
Sent:	Tuesday, August 3, 2010 07:51:21
From:	Ollie Townsend III (
I have a friend who is using the telescope and he is planning on getting
an Android phone.  (Currently using a Windows Mobile version) I am a
small time Android app developer and I would like to be able to give him
a hand (and of course I would get the thrill of learning something new)
and create an app for him to control the telescope with the phone.  Is
there a chance you could point me in the right direction on where to
look to start my project?  Thanks in advance!

Ollie Townsend III | NetApex |
Twitter: | GVoice:419.318.9828
Google Wave:
Mike here: If you are writing for the Meade telescopes that use the AutoStar handcontroller, there are some articles on AutoStar commands on the Helpful Information: AutoStar Info page on my ETX Site. If you are writing for any other telescope, see the manufacturer's web site for programming information.


Sorry, forgot to specify which device.  Yes it is a Meade that uses
AutoStar.  I will head to your site to see what I can find. Thanks.

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