                  SatLink Satellite Communications Program
                         by Jesse Buckwalter, NZ3F

SatLink is a character-based (read non-Windows) replacement for PB and PG.
Additionally, SatLink provides a simulation mode with which the user can
demonstrate many of the SatLink functions without actually receiving satellite
transmissions.

SatLink is compatible with PB data files.  SatLink directory files are names
PB__????.PFH.  SatLink uses an SLIST.DAT file with the same format as PB.
All .HOL and ACT. download files are identical to those that PB produces,
as is the PFHDIR.HOL file.   The help file is named SATLINK.HLP, but the format
is the same as PB.HHH.

To set up SatLink:

1.      You can put SATLINK.EXE anywhere.  If it is in a subdirectory that is
in the DOS directory search path, then you do not need to qualify SATLINK.EXE
when you execute it.  Otherwise, you must fully qualify SATLINK.EXE with a path
or change to the subdirectory where it resides.

2.      Modify the example SATLINK.CFG file.  You can name the file anything
you wish and put it anywhere.  You will need one version for each satellite
as you do with PB.

Most of the parameters are very similar to those that PB uses.  However, there
are a number of additional parameters.  Please review the example SATLINK.CFG
file.  There are three subdirectory paths that you can specify.  These are:

        workDir - where SatLink puts the PB__????.PFH files, SLIST.DAT,
                  PFHDIR.HOL, and expects to find the SATLINK.HLP file.

        dlDIr -  where SatLink puts *.ACT, *.HOL, and *.OHL files.  SatLink
                 also puts *.CAP files (screen capture) and *.SLP (SLIP files,
                 know as *.KSS files by PB) in this directory.

        ulDir - where SatLink looks for *.OUT and *.PUL files to upload.

3.      Modify any INIT.TNC and TERM.TNC files that you require.  These are
optional and SatLink will use them only if it finds them.  You must specify
the path and file names that you are using in the configuration file.

I recommend that you initialize the TNC so that it doesn't monitor anything.
SatLink does everything using the KISS mode.  Some TNC's have a hard time
switching between what I call Terminal Mode and KISS Mode when the TNC is
receiving lots of data.  Data reception preempts mode switching.

4.      Execute SatLink:

[path]satlink[.exe] <configuration file path/filename>

A configuration file MUST be included.  There is no default.  Any valid name
is acceptable.

5.      The SATLINK.HLP files describes the SatLink keystrokes.

6.      Running SatLink in the simulation mode.

Set the "simulate" parameter in the configuration file to 1.  Put a data file
named *.SLP in the "dlDir" subdirectory specified in the configuration
file.  You may use an *.KSS file created by PB and rename it to *.SLP or an
*.SLP file created by SatLink.  The *.KSS and the *.SLP files are essentially
the same except the .SLP files may also contains data SENT by SatLink as well
as data received by SatLink.  This includes KISS commands to the TNC, so be
aware that KB5MU's "kissfilt.exe" program will not work correctly with *.SLP
files.  See the "log" parameters in the example SATLINK.CFG file.

If you have a fast computer, you can slow things down by using the
"simulationDelay" parameter in the configuration file.  Alt-P will pause
the simulation.  Successive Alt-P keystrokes will step the program by
processing approximately 512 bytes of data at a time.

If you have "logInFrames" during a pass in which you uploaded a file, the *.SLP
file will contain the connected-mode responses to you from the satellite.  If
you have files ready for uploading in the "ulDir", SatLink will simulate a
connected mode upload.

7.      You can switch between Terminal Mode and KISS Mode by pressing
Alt-T and Alt-K respectively.  This has little value.  However, if you cannot
do this manually, then SatLink cannot successfully do it automatically.  The
same code is executed whether modes are switched manually or automatically.
Note:  If you switch in the middle of a "hot" pass, you may not be able to
switch back for the reason mentioned earlier.

Commentary:

This program is for general distribution.  Feel free to use it, and please
report any problems.  I will endeavor to correct problems, and I will consider
requests for enhancements as time allows.  SatLink seems to be reasonably
stable, however, I have made many coding changes.  Therefore, I may have
introduced problems where they did not exist in the 950120 version.

At some time I will release the code for this program.  I hope to release a set
of C++ object classes that are reusable and obviate some difficulties that
frequently occur with code reuse.  I am currently working on rewriting the code
to achieve this objective.

Jesse Buckwalter, NZ3F
525 Third Street
Annapolis, MD  21403, USA

Pacsats:  ko-23, ko-25

Internet:  nz3f @ amsat.org
           jebuckwalter @ attmail.com
