Cream of the Crop 1/Cream of the Crop 1.iso/BUSINESS/SOP9228A.ARJ/STSPLUS.NEW

Text File | 1992-07-08 | 15KB | 247 lines

   STSORBIT PLUS Revision History
   ------------------------------

         Each released version of STSPLUS uses a four digit revision code such
   as 9218. The first two digits indicate the year and the second two digits
   indicate the week of the year. In some cases, an additional letter suffix
   is added to distinguish changes occurring within the same week or to
   identify special versions. A partial week at the beginning or end of the
   year is counted as a full week. Using this method, a year will typically
   have 53 weeks although it is possible to have 54 weeks in a leap year (1972
   is an example). The current year-week revision code is shown on the Julian
   Date display, Display Mode 7, in my program ASTROCLK.
        This file records the revision history of program STSPLUS through all
   of the minor twists and turns that usually accompany the evolution of such
   a complex program.  It illustrates the tortuous process of maintaining and
   refining a program as ideas and problems are reported from every quarter.
   These notes may also be helpful to users who are upgrading from one version
   to another to find out what has changed.

                                                 David H. Ransom, Jr.


   Version 9228A -- July, 1992
   ---------------------------
   -In response to many user requests, I have improved the 2-line elements
   file directory functions using F2 from the Main Menu. The list of available
   files is now alphabetized and you may use the ARROW KEYS to move through
   the list. The selected file is highlighted and is shown as the new default
   file. See the section "F2  Read NASA/NORAD 2-Line Elements" for a complete
   explanation.
   -Corrected a bug that displayed the incorrect city label for the primary
   location if the Location Map for the second location was last displayed.
   Thanks again to Joel Runes for spotting this one!
   -Corrected a minor bug that caused the "BAD CHECKSUM ..." error message to
   scroll off the screen when reading 2-line elements (F2). The message now
   appears in RED following the File Record Number.


   Version 9228 -- July, 1992
   --------------------------
   -Fixed bug when too many .TXT files were present and the list overflowed
   the available screen columns and aborted with "BASIC PDS Error 5". The file
   listing now stops when the screen is full (and some files may therefore NOT
   be displayed).
   -Changed screen mode for EGA and VGA monitors to use 43 or 50 lines for
   display of available .TXT files. Screen returns to 25 lines after file
   search. This slows the display slightly but greatly increases the number of
   files that may be displayed on EGA and VGA systems.
   -Fixed bug associated with help screen (F1 with the map displayed) which
   caused big clocks to overwrite the help information and then display only
   changed digits when F1 was pressed again.
   -Changed the satellite elements data display shown when selecting 2-line
   elements to add the acceleration/drag and to move the Element Set Number to
   the top of the data for clarity.
   -Changed colors for satellite position data (Range, Altitude, Azimuth, etc.
   at the right of the data block) such that when the satellite is in view of
   the current location, the color is LIGHT GREEN, otherwise YELLOW (all map
   modes except TRACKING STATION) or LIGHT RED (TRACKING STATION).
   -Corrected Location Map so that the primary location and name are displayed
   when the map is centered on the secondary location.


   Version 9227C -- June, 1992
   ---------------------------
   -This version NOT released publicly.
   -The Big Clock mode has been added for all display monitors -- for those of
   us who want big characters due to impaired eyesight. This displays UTC date
   and time, Local date and time, or MET/T+Epoch in large characters and is
   enabled by Function Key F2 (see following item).
   -Changed the operation of Function Key F2 while map is displayed. Instead
   of controlling the satellite blink (which may now only be controlled by the
   "B" key), F2 now selects the Big Clock mode. The Big Clock modes are
   selected in the following order:
        0    No clock displayed
        1    UTC date and time
        2    Local date and time
        3    MET or T+Epoch (select with F5)
   -Note that not all computers (especially older CGA systems) will display
   the extended graphics characters used for the large clock characters. The
   symptom of this problem is that the lower left portion of the data block is
   mostly blank after pressing F2. If you have this problem and your computer
   is running DOS 3.x or DOS 5.0, enter the command "GRAFTABL" at the DOS
   prompt before running STSPLUS or include the line "GRAFTABL" in your
   AUTOEXEC.BAT file; this sets the "code page" to enable the computer to
   display the extended graphics characters. [The program GRAFTABL.COM is
   included as part of DOS in most cases.]
   -Changed the extended clock feature to use command line option "/CLK"
   instead of "/60". In this mode, the text portion of the map display uses 43
   (EGA) or 60 (VGA) lines instead of the normal 25 lines and positions the
   clocks below the normal data block. This feature now operates correctly on
   both EGA and VGA systems but when enabled, the Motion Map is disabled.
   -Various minor cosmetic changes.


   Version 9227B -- June, 1992
   ---------------------------
   -Corrected persistent bug present in Versions 9226/9227/9227A which caused
   the program not to recognize Hercules (HGC) monitors even after MSHERC was
   executed. Thanks to Roger Guilemette for reporting the problem.
   -Corrected problem when second location was present and displayed on the
   Location Map. Switching back to World/Quadrant/Zoom maps gave altitude and
   aximuth data for second location instead of standard location.
   -Corrected Location Map for second location to remove overprinting of the
   local name on top of the second location's name. Thanks to Joel Runes!
   -Moved location names to above location in the Location Map to avoid
   overprinting the altitude data.
   -Added circle of visibility for second location (if present).
   -Modified the block number "5" so as not to be confused with "6".
   -Various minor cosmetic repairs.


   Version 9227A -- June, 1992
   ---------------------------
   -This has NOT been a good day. Just as soon as I released Version 9227,
   another bug was reported. Versions 9226 and 9227 will not execute on an EGA
   system, reporting that they do not recognize the monitor type. This has now
   been repaired. Thanks to Roger Pettengill for reporting the problem!


   Version 9227 -- June, 1992
   --------------------------
   -Removed a "Clear Screen" that caused the MOTION MAP not to work in Version
   9226. It never fails that I seem to break something while fixing something
   else. For some reason, that got missed in testing ... sorry!
   -The standard program version now can be used in Read/Only Networks. Set up
   the program the way you wish, then edit STSPLUS.INI so that the version
   number on the first line is negative, e.g. "-9227" instead of "9227". With
   the STSPLUS.INI file set up this way, the program will NEVER write a new
   Remind users to use the command line "STSPLUS /R" for immediate startup.
   -As an experimental test, VGA users ONLY may include the command line
   option "/60" to force 60-line mode and display a large clock at the bottom
   of the data block. (Not yet configured for use with the Motion Map!!)


   Version 9226 -- June, 1992
   --------------------------
   -Corrected (I think) a problem in zoom mode which caused the program to
   hang on startup using the command "STSPLUS /R" if the time was prior to the
   time of epoch. Thanks to Joel Runes for reporting this one!
   -Corrected a bug with higher inclination orbits which caused the map to be
   redrawn repeatedly near the poles. I've only seen the problem with orbit
   inclinations greater than 60 degrees AND with automatic map generation
   enabled. The problem was related to the map centering and map projection.
   -By popular request, I've restored the "feature" which allows the user to
   interrupt map drawing by pressing ENTER. This slows down map drawing
   slightly but so many folks have complained since I removed it ...
   -Corrected the circle of visibility algorithms to correctly plot circles
   which overlap a pole. The "overlap" portion of the circle appeared near the
   opposite pole instead of where it belonged! Thanks to Don Nicholson for
   pointing out the error!
   -Because of frequent user complaints, setting fast time (X10 or X60 using
   F4 while the map is displayed) will now disable automatic map generation. I
   recommend using fast time ONLY on the world map, or using it when PAUSE is
   enabled. Press TAB to restore automatic map generation.
   -Changed the algorithm for calculating orbit numbers to account for the
   drag and other effects that caused the orbit number calculation to fall
   behind by approximately 0.1 orbits every 15 days (measured from the Epoch
   of the elements) for satellites in low Earth orbits. The "new and improved"
   algorithm is now accurate to better than 0.01 orbits when the simulation is
   started for either real or simulated time (SLOW MODE not enabled).
   -If the SLOW MODE is enabled, the new orbit number algorithm is only used
   when elements are loaded ("/R" command line option or F2 from the Main
   Menu) to avoid additional processor delays. In SLOW MODE, the initial
   calculation is done once for real time and some error will be noted in the
   orbit number if simulated time is set days different from real time.
   -Corrected a 1 pixel vertical error in plotting which occured under certain
   circumstances. The TDRS satellites, for example, were sometimes plotted 1
   pixel above the equator.
   -Improved the map centering logic to avoid an occasional incorrect map
   center (usually quadrant maps) which was followed by an immediate redraw.
   -Improved ascending and descending node logic to (hopefully) eliminate
   spurious data which was displayed under certain circumstances.
   -Fixed a minor bug in printer output where five digit orbit numbers were
   incorrectly displayed as "%11007" instead of "11007".
   -In response to user requests, I have added an additional status message,
   "Recalculating Map and Position data ...", which appears on what was
   previously a blank screen before the actual map is drawn. The message
   doesn't even appear on my 486/33 but is visible for about 15 seconds on a
   vintage 8MHz 8088 with no coprocessor.
   -Repaired a minor bug that set the default satellite name to the last
   satellite found in a file when the satellite being searched for was not
   found. The original satellite default name is now restored correctly.
   -Repaired the demo (F1 on the Main Menu) so the correct mission name and
   icon are used. The "countdown" may now be terminated with ENTER.
   -The format of the data printed with the LOG function has been changed to
   avoid numeric overflow of the ORBIT field and the columns changed. The
   NORAD number has been added to the initial data block.
   -Only minor updates and changes to the main documentation.


   Version 9219 -- April, 1992
   ---------------------------
   -Version 9219 corrects a minor bug in the circles of visibility for the
   user's location, the alternate location, and the tracking stations. These
   circles were incorrectly shaped in Version 9218 due to a minor error in the
   formula that crept in during testing. (The circle of visibility for the
   spacecraft was correctly shaped and all numerical data was correct.)
   -Versions 9204 through 9218 ignored bad checksums in 2-line elements but
   did not read the data correctly. This has now been repaired and a bad
   checksum on either data line is reported but otherwise ignored and the data
   read correctly.
   -Several minor typos were corrected in this documentation.


   Version 9218 -- April, 1992
   ---------------------------
   -Version 9218 is the initial formal release of program STSORBIT PLUS and
   now includes complete program documentation. The beta releases included
   only update notes to the original STSORBIT 9134 documentation. While the
   STSORBIT PLUS documentation borrows heavily from that original STSORBIT
   documentation, many sections are new or have been rewritten and updated.
   -I had planned to modify STSPLUS for dual satellite operation but this
   proved more difficult than expected. After many hours of work, I have put
   that feature aside, at least for the present. The basic structure of the
   program does not lend itself to multiple satellites; this is particularly
   true of the multi-layered graphics features. The processor workload was
   also increased substantially, making things even more difficult for the
   many users without a math coprocessor chip. Finally, given the other
   demands on my time, a complete rewrite from scratch would simply require
   too long. I'm sorry to disappoint those who asked for that feature ...
   especially the folks working on Mission STS-49.
   -In order to eliminate problems due to changes from one program version to
   another, STSPLUS now ignores all data from different versions of file
   STSPLUS.INI and the program must be initialized as if being run for the
   first time. Only .INI files written by the same program version will be
   accepted. Trying to maintain backward compatibility with all prior versions
   of the .INI file has become both difficult and time consuming -- and has
   not always been successful. Too many problem reports have been due to
   corrupt or incompatible .INI files, sometimes from versions dating back
   several years.
   -There have been many changes from Beta Version 9206, too many to describe
   in detail here. Even "seasoned users" of STSPLUS should check this
   documentation carefully!


   Beta Versions 9139 thru 9206
   ----------------------------
   -Beta versions released for testing and comment. Version numbers included
   9139, 9145, 9146, 9148, 9202, 9203, 9204, and 9206. Significant changes and
   improvements were incorporated in these releases, often the result of user
   feedback. Many thanks to those who sent in bug reports and suggestions!


   Beta Version 9137 -- September, 1991
   ------------------------------------
   -Initial public beta version.