Category : Assembly Language Source Code
Archive   : DOCFILES.ZIP

Output of file : WAITASEC.DOC contained in archive : DOCFILES.ZIP

WAITASEC (and SCROLL) Charles Petzold
Command(s) PC Magazine Vol 4, No 24
Copyright 1985 Ziff-Davis Publishing Company

Purpose: Uses the single-keystroke ScrollLock key to
halt a fast-scrolling display; then allows
you to scroll backwards, recalling previous

Format: WAITASEC (loads memory-resident program)
(activates command)

Remarks: WAITASEC is a memory-resident program that is
normally loaded through your AUTOEXEC.BAT
file. Thereafter, alternately pressing and
releasing the ScrollLock key will halt and
restart a scrolling display, e.g., a lengthy
DIR listing.

While holding down the ScrollLock key to
freeze the display, if you also press one of
the cursor movement keys (Home, Up Arrow,
PgUp, End, Down Arrow, or PgDn), the display
will not resume scrolling when you release
the ScrollLock key. Thereafter, the Up and
Down arrow keys move the display by one line,
the PgUp and PgDown move it by 25 lines, and
the Home and End keys take you to the
beginning and end of the stored screen
memory. Pressing any non cursor key at this
point deactivates the stored mode, and the
original scrolling resumes.


1. WAITASEC will not work with an 80-column
color/graphics display if an unmodified
PC-DOS ANSI.SYS has been loaded. (The
ANSI.SYS that comes with various
versions of MS-DOS does not cause
problems with WAITASEC.) To run with
IBM's ANSI.SYS, make a copy
(MODANSI.SYS) of the original ANSI.SYS
and use DEBUG to patch the copy as

E 29D 90 90
E 2A1 90 90

Put the modified MODANSI.SYS in your
CONFIG.SYS file in place of ANSI.SYS.

2. Because of the way they handle TTY
output, certain EGA cards will not
permit WAITASEC to scroll backwards.
This problem can often be cured by
adding MODANSI.SYS, as above.

3. WAITASEC does not save your current
display screen. To save your current
display, before beginning a scroll,
enter the complementary SCROLL command,
and everything on the screen will scroll
off the top and be captured in the
WAITASEC buffer.

4. While WAITASEC has been found compatible
with XyWrite III (XYKBD.COM loaded) on a
PC AT, as with other memory-resident
programs, unforeseen hardware and
software incompatibilities may be

  3 Responses to “Category : Assembly Language Source Code
Archive   : DOCFILES.ZIP

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