Bit-Imaging With Word Processors - Epson 8133 User Manual

Line 30 sets a line length for printing 80 characters. This means
that the carriage return and line feed sequence is added by the interface
after 80 characters have been received. They are then interpreted as bit
image characters affecting the image which is printed. Since the
printer has received two extra characters the last two characters which
were intended as bit image data are no longer seen as being part of the
bit image sequence since they come after the allocated number. The
first is a CHR$(44) which is a comma. The last is a CHR$(12) which is a
form feed. If you run the program you will see that the paper is fed
through the printer at the end of printing.
This problem can be overcome by removing line 30 altogether, or
by setting the width of the line to 255 characters while the bit imaging
is carried out. You can do this using <CTRL>-1 255N instead of
<CTRL>·l 80N. Note also that, in line 40, the LSB has of necessity
been sent using the command <CTRL>-1175<. This is because the
Apple normally sets the high bit of characters which you print to zero:
transparent mode is provided to stop this from happening. If CHR$(175)
had been used as part of a PRINT statement, it would have been sent to
the printer as ASCII code 47, i.e. 175-128. This would mean that only
47 characters would have been printed as bit image data, and from then
on the remaining bit image data would have been printed as a series of
commas and form feeds.
This type of problem, in which data is printed as normal characters
when you still expect bit image characters, and the reverse one in
which bit imaging continues when text should be printed, is not
normally the fault of the APPLE or the interface. It is usually due to
miscalculation when the number of data bytes for the bit image data
are worked out.
BIT IMAGING WITH WORD PROCESSORS.
11111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111
Programs which will accept control commands, like Zardax and
AppleWriter II or Ile are able to print bit image characters via
the# 8133 interface. For instance, in the case of Zardax, to print the
'Venus' character used in the BASIC program above, simply enter the
ordinary edit mode then press <CTRL>· • I and immediately follow this
with the sequence of characters 12>1B4B080022528A8F8A522200, as in
the BASIC example. In a similar way, AppleWriter
JI
is able to accept
control commands via its <CTRL>-V option. In this case, enter
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<CTRL>·V <CTRL>-1 <CTRL>-V and follow it immediately with the
sequence given above. Of course, it is possible to create your own
sequence of bit images in this way too and you could enter your bit
image data as items in the word processor's glossary, so that they are
always readily available.
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