Producing Text Screen Dumps; Sending Characters Direct To The Printer - Epson 8133 User Manual

PRODUCING TEXT SCREEN DUMPS
11111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111
The currently active text screen can be printed out by giving the
command:
1111111111111111111111111111111
SENDING CHARACTERS
1111111111111111111111111111111
DIRECT TO THE PRINTER
<CTRL>-lnS
Then is an optional parameter controlling which of the two text
screens is dumped on an APPLE Ile: if you have an APPLE II or an
APPLE II+, only 40-column screens can be dumped and then can be
left out. On the APPLE Ile, no matter which screen is currently
active, you can given a value greater than 127 to print out the
80-column screen, or less than 128 to print out the 40-column screen.
The following program illustrates how the command works on an
APPLE Ile:
command purpose
Because of the way the APPLE system software has been written,
and the fact that some characters are used as control characters by the
computer monitor, BASIC and DOS, it is not normally possible to
send all the ASCII codes directly to the printer. This is an example of
the many problems which occur as a result of the APPLE II being one
of the first generation of microcomputers. Like all difficulties of this
sort, there are ways around it. In this case, the Epson #8133 Interface
provides three commands for different occasions:
20
PRiNT
25 �: E M
CHR$
!9);"1285"
PRINT 40-CDL SCREEN
<CTRL>-1
n<
<CTRL>-1
n>
<CTRL>-1 nT
<CTRL>-1 H
<CTRL>-1 X
allows you to send one character with ASCII code
n
directly to the printer
allows you to send a series of
n
characters
represented by ASCII equivalents of hexadecimal
bytes
allows
n
characters to be sent directly to the printer
as data with no interception by the # 8133 interface
converts data with ASCII code
n,
where n<l28, to
n+l28
converts data with ASCII code
n,
where n>I27, to
n-128
30 PRINT CHRS (9);"15''
5 REM PRINT CURRENT TEXT SCREEN
10
PRINT CHRS 191;"5"
15 REM PRINT 80-COL SCREEN APPLE IIE ONLY
30
<CTRL>-1
n<
sends the character whose ASCII code is
n
as a single 8
bit byte. You would give the character as the decimal equivalent of its
code. For example, the command:
<CTRL>-1 27<
will send the character whose ASCII code is 27 (decimal). This is
useful where you know the code for the character which is one which
might cause a problem and therefore cannot be input directly from the
keyboard.
31