Apple Grr - Manual (Page 4)

appear like a negative photograph. Using this
command will print the black portions of the screen as
black on the paper allowing the picture to appear
nornrrally.
L — Print the image at the left margin previously set
using the left margin text command. Depending on the
type of printer being used, this margin may be affected
by the current print density (characters per inch) or may
be automatically set to 7 dot positions per character. If
this option is not used, the image will be printed in the
center of an 8V2 inch page.
R — Rotate the picture 90 degrees in a clockwise
direction. Some printers require this option when printing
the image double size. (See D above).
An example of a graphics command would be CTRL-1
GDIR2 followed with a carriage return. This will print the
inverse of HIRES page 2, double size, rotated
90 degrees. Options may be listed in any order, as long
as they are preceded by a CTRL-1 G and followed by a
carriage return. Care should be used when using the
“L" specifier. If too large of a left margin is used, the
picture may wrap around or, depending on the printer,
it could cause it to “crash" and then both the computer
and printer would have to be reset (see “D” on previous
page).
Note: When typing Grappler commands directiy from
the keyboard (not from a program), the Apple will give
a syntax error. This is normai since Applesoft doesn't
recognize this as a valid command. However, the
Grappler will still recognize the command. To avoid the
syntax error, type a one line program. For example:
10 PR'»'!: PRINT CHR$(9);"G'':PR*0
Then type RUN.
CHART RECORDER MODE
A chart recorder prints a continuous graph on a roll of
paper. If you need to chart more information than can
be done on a single HIRES screen, you can simulate a
chart recorder by printing successive screens without
any intervening spaces. The type of printer you are
using will determine whether this can be done with
normal or rotated images. In general, if your printer
prints six graphics dots at a time (e g. IDS Paper Tigers,
Centronics 739, Anadex 9500-9501), if you will be using
successive normal (horizontal) screen dumps, or if your
printer prints even seven dots at a time (e.g. Epsons,
NEC 8023), you will be using successive rotated screen
dumps.
PASCAL AND CP/M COMPATIBILITY
The Grappler is compatible with both PASCAL and
CP/M. PASCAL 1.0 and CP/M will both recognize the
card as a serial interface. Entry points have been
provided to mimic a serial interface so that the card will
function properly with these systems. PASCAL 1.1 will
correctly interpret that it is a firmware printer interface
and access it accordingly. In either case the card will
function normally with a few minor exceptions as
detailed on the following page.
Since both systems use a CTRL-I to represent a
horizontal tab, the default command character has »
been changed to CTRL-Y. If you are listing a file that
contains tabs, be certain the printer tabs (see your
printer manual) have previously been set.
PASCAL does not use any of the monitor routines. For
that reason do not try and turn on the screen with a
CTRL-Y I command or do a text screen dump (CTRL-Y S).
Either one will “crash" the system and both the
computer and printer will have to be reset.
Both PASCAL 1.0 and CP/M use one of the I/O Ram
locations to pass the output character. Since the
Grappler was already using all available locations for its
variables, the right margin function had to be deleted
to make it compatible. This feature is still available from .
BASIC or
pascal 1.1.
FOR ADVANCED PROGRAMMERS:
MEMORY LOCATIONS USED BY THE GRAPPLER
The Grappler Interface uses those RAM locations set
aside for its particular slot and the slot scratchpad area
common to all slots. The ROM is turned on using the
standard ROM expansion protocol and resides in the
locations SC800 to SCFFF. The entry points and the
various RAM variables are listed below (N=Slot number):
Cold Entry = SCNfJ®
Warm Entry = SCN02
Left Margin = S478 + $0N
Right Margin = S678 -t- S(3N
Line Length = $578 + SUN