Apple Computers

The Apple II computers present two problems when using them with a printer like the SQ-2000. First, they can only send seven bits of data to the printer, and second, they use the code ASCII 9 for internal initialization of the printer routines.

The seven-bit limitation presents the largest problem, but we have two solutions to offer. The easiest, but more expensive, solution is to purchase a printer interface card that addresses all eight bits. Your Epson dealer will help you with this.

The other solution is to POKE codes directly to the printer output port on the Apple II. You can use the following routine to do this on an Apple II Plus computer:

100 IF PEEK(49601)>127 THEN 100

110 POKE 49296,N

where N is the code that you want to send to the printer. Line 100 checks the printer’s status and line 110 sends the code to the printer.

The Apple II used ASCII 9 to initialize the computer’s printer routines. This code and the following character or characters are intercepted by the printer interface card and used to change the modes (in somewhat the same way the printer uses escape codes). You can divert all output to the printer instead of to the screen by sending the following lines to the printer interface card:

PR#1

PRINT CHR$(9) "80N"

Then type anything, followed by ENTER.

The CHR$(9) “BON” directs all subsequent output to the prin- ter, up to 80 characters per line. You can cancel this by typing:

PRINT CHR$(9) "I" or PR#0

To avoid the problem with ASCII 9 you can change the printer initialization code to something else; this frees the ASCII 9 to go on to the printer. This routine will change the printer initialization code to ASCII 1:

PR#1 PRINT

CHR$(9); CHR$(1)

90