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If you select near letter quality, the character box is the same size but
now has 16 (high) x 23 (wide) dot positions. Each dot is represented by two
adjacent sharp signs, occupying its own position and the position to the right.
This reflects the fact that the printer still cannot print horizontally adjacent
dots, but that even skipping every other dot, the dots appear joined when
printed.
A near-letter-quality
character is represented by 46 bytes of dot data,
two bytes for each column. Near-letter-quality
characters are printed in two
passes of the print head, the paper scrolling half a dot up between the passes.
The first 23 bytes of dot data represent the first pass; the next 23 bytes
represent the second pass. In each column the first, third, fifth, . . . dots belong
to the first-pass byte and the second, fourth, sixth, . . . dots belong to the
second-pass byte.
A maximum of 78 near-letter-quality
characters can be defined.
The file created by this program contains the following printer com-
mands:
1.
< ESC > ":" CO> <O>
<O> (standardmode)or
<FS>
":" <O>
< 0 > < 0 > (IBM mode) to copy the printer's regular characters into
download memory. If you leave a download character undefined, the
regular character will be printed.
2.
< ESC > "x" < 0 > or < ESC > "x" < 1 > to select draft or near letter
quality.
3.
One <ESC>
"&" <O> <cc>
<cc>
<a>
<pl>
. ..commandfor
each character defined. < cc > is the character code, < a > is the attribute
byte, and <pl > . . . are the 11 (draft) or 46 (near letter quality) bytes
of dot data. This program uses only the most significant bit of the at-
tribute byte. It does not set the other bits, which are concerned with
proportional
spacing.
This program is coded in Microsoft BASIC for IBM-PC. The WIDTH
255 command
in line 1010 means infinite line width and prevents the
computer from inserting unwanted line feeds in the character data. Some
_
versions of BASIC do not need the WIDTH command.
Check your BASIC
manual and make any changes necessary.
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Table of Contents
Troubleshooting
