InstantTrack provides a mechanism that makes it easy to let another program update the Keplerian elements database maintained by InstantTrack. This tutorial shows you how to set this up under MS-DOS using WATTCP FTP to download elements from the AMSAT.ORG web site.
This tutorial assumes that you already have an Ethernet home network set up, with shared access to the Internet, and that you know a little bit about computer networking. It's far beyond the scope of this tutorial to explain how to set all that up.
I am assuming that you have a separate machine running MS-DOS for InstantTrack. It might be a dedicated machine, or it might be a machine you sometimes boot in MS-DOS and sometimes in Windows or another OS. If it's a separate machine running DOS, I guess you probably don't have it on your network yet. So, I am detailing some of the procedures for adding minimal networking capabilities to your DOS machine.
Forgive me if some of the instructions are too basic for you. I am assuming that you might be expert at Windows but very unfamiliar with DOS.
If you are running InstantTrack under Windows, don't use this procedure. There are easier ways, taking advantage of the built-in networking capabilities of Windows. See for instance the tutorial on using cURL.
Your DOS machine will need an Ethernet card to connect to your home network. This application doesn't need a lot of speed or fancy performance, so nearly any Ethernet card will do. Take note of the following considerations in choosing an Ethernet card:
Turn off your DOS machine, open it up, and stick the card in an available slot.
If you already have an Ethernet card in the machine, of course you'll skip steps 1-3.
Older Ethernet cards will have physical jumpers to set. Modern Ethernet cards will require you to run a special program that came with the card to configure it. Read the documentation and figure out which you need to do. You may have to wrestle with DOS arcana like interrupt numbers and I/O addresses, but if you're lucky it will be pretty automatic. If not, there are too many considerations for me to cover here. If you run into trouble, I suggest you find local help from somebody technical who has been around PC's for a long time. Or find some old PC hardware books in the used bookstore and study up.
Most Ethernet cards come with a self-test utility program. Run it and make sure the card is working before proceeding.
Locate the packet driver software for your Ethernet card. It will probably be on the disk that came with the card. If not, you can probably download it from the manufacturer's web page. If not, try the Crynwr web page.
Copy the packet driver itself (the
.EXE file) into a
convenient directory. It doesn't matter where, just remember where
you put it for a minute.
AUTOEXEC.BAT file and add a line that calls the packet
driver. If the packet driver is named
PKT8000.EXE and you put it in
then the line you need to add looks something like this:
Notice that there are some extra arguments after the program name.
These arguments will vary from packet driver to packet driver. You'll
have to read the documentation to find out what to put there. In the
above example, the only mandatory argument is the "software
interrupt" number, and the value
0x7e is the one I arbitrarily
chose to use. You have to pick a value between 0x60 and 0x80.
Of course if you're already using the Ethernet card under DOS, perhaps with KA9Q NOS or one of its variants, then this has already been done and you can start at step 5.
Download this program: FTP07.ZIP and unzip it
into the InstantTrack directory,
(or into some other directory on your PATH).
Create a plain text file called
WATTCP.CFG, and put it in the same
directory as the FTP program.
Consult the documentation file
that came with the program for details. This is where you will have to
know a little bit about networking. You'll need to put the details of
your home network in there, including the IP address you want to assign
to the DOS machine, and the IP address of the gateway machine on your
To be sure you have everything set up right, run the FTP program at a DOS prompt by typing:
c: cd \it ftp
The program will respond with a little welcome message, like this:
FTP Transfer Program Version 0.70 Type HELP for more information FTP>
If you see any other messages, there is probably a problem with your installation. Solve those problems before proceeding.
That last line is the FTP prompt, where you can type interactive commands to the FTP program. Type the following:
Those numbers are the IP address for ftp.amsat.org. Really you should be able to type the name ftp.amsat.org instead, but I couldn't get that to work with the WATTCP FTP program. Those numbers can change, but not very often, so it's not a big problem to use the numeric IP address.
If all is well, the FTP program will respond with this:
trying '22.214.171.124' [126.96.36.199] 220 amsat.org FTP server (Version 6.00LS) ready. Userid :
Don't enter your own user name. This is going to be an unauthenticated transfer, so you don't need a name. Instead, enter the special name:
At the password prompt, enter your email address, or actually anything with an @ in it.
230 Guest login ok, access restrictions apply. FTP>
That's enough for a test, so type:
You don't want to go through all that each time, so we'll automate it. Create a plain text file called GETKEPS.FTP in the InstantTrack directory, and put this in it:
open 188.8.131.52 anonymous ituser@amsat cd /amsat/keps/current get nasa.all quit
This script will walk the FTP program through the steps of downloading the Keplerian elements.
To make it even more automatic, we'll make a batch file to run the whole update. Create a plain text file called GETKEPS.BAT in the InstantTrack directory, and put this in it:
ftp -f getkeps.ftp it /f nasa.all exit
This runs the file transfer, and then feeds it to InstantTrack.
If you want, you can add a line before exit that runs InstantTrack again, so you can use it right away.
ftp -f getkeps.ftp it /f nasa.all it exit
If you normally run
ITNCP instead of
IT, then substitute
IT in the batch file, too.
Whenever you want to update the Keplerian elements, just
CD to the InstantTrack
directory and type
and all the stuff we just set up will fire up and do it all for you.
IT.ORB file will be updated only if there are newer
elements in the downloaded file. Don't let this confuse you when testing
out your batch file. The date and time on the
IT.ORB file won't change
every time you run the batch file. You can force it to change by running
InstantTrack and deleting the elements for one of the satellites in the
downloaded set. That way, the automatic update will need to re-add that
satellite, forcing it to update the
Last updated 9 May 2003. Comments to KB5MU, firstname.lastname@example.org
Copyright 2002-2003 Paul Williamson. All Rights Reserved.