Each released version of JPLCLOCK uses a four digit revision code
such as 9126. 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. 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 year-
week revision code for any date may be determined using the Julian Date
display, Display Mode 7, in my program ASTROCLK.
This file records the revision history of program JPLCLOCK through all
of the minor twists and turns that usually accompany the evolution of such
a 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.
-By popular request, I have added a screen blanker function which will turn
the screen off five minutes after the last keystroke. To enable or disable
the screen blanker, use Function Keys F4+F5 from the Main Menu or ALT-F2
while the clocks are displayed. The screen blanker is DISABLED by default
and the status is preserved in STSPLUS.INI. Unlike most screen blankers,
however, this one restores the screen just before the half hour, at 29 and
59 minutes past the hour, or press any key.
-By popular request, I have added Function Keys F3+F4 to enable or disable
the display of Mission/Event Timer numbers at the lower left of each timer
window. This function is DISABLED by default. These numbers can be helpful
during Launch Support and to quickly identify a Mission/Event Timer number
from the active display.
-By popular request (yet another one!), I have added the PgUp and PgDn keys
as active when PAGE mode is disabled (the display is "frozen" to a single
page of Mission/Event Timers). Previous versions always displayed Page 0 in
this mode; JPLCLOCK may now display any active page by the use of PgUp and
PgDn. This status is NOT saved from one execution to the next.
-The "thermometer" above the Mission/Event Timer windows is now displayed
at all times, showing the current page and which pages have active timers.
Pages normally are indicated in GREEN (active and past Time Zero), RED
(active and not yet to Time Zero), and GRAY (not active). When PAGE mode is
active, the current page is flashing and all other pages are steady; when
PAGE mode is NOT active, the current page flashes MAGENTA to so indicate.
-In order to facilitate network operations, the filename (optionally
preceeded by the path) for the text message file has been added near the
end of JPLCLOCK.INI. Since the default is "JPLCLOCK.INI" (and note that it
should be enclosed in double quotation marks), it is easy to recognize. Use
any editor in the ASCII or non-document mode. The file is now reloaded each
time at the beginning of the first text page and may therefore be replaced
with a new file from time to time without halting program execution.
-Various minor cosmetic changes.