Some users have discovered that when they try to create custom characters
with the ImageWriter I and II printers, the resulting character is always
underlined -- whether they want it that way or not.
The Apple ImageWriter I and ImageWriter II printers -- as well as the Apple
Dot Matrix Printer -- have special modes that allow them to generate
custom-design characters. For the most definition on each character, it is
useful to control all eight data bits sent to the printer.
This Applesoft BASIC program has been tested for the underlining problem,
and will work correctly (that is, the character will appear as desired):
10 D$ = CHR$(4)
20 FOR I = 768 TO 773: READ J: POKE I,J: NEXT I
30 PRINT D$;"PR#1"
40 FOR I = 1 TO 14: READ J: POKE 769,J: CALL 768: NEXT I
50 PRINT CHR$(27)"*&&&" CHR$(27)"$"
60 PRINT D$; "PR#0"
70 DATA 169,4,76,237,253,96
80 DATA 27,45,27,73,166,71,0,72,72,126,72,72,0,4
Line 20 reads the data from line 70, and POKEs a machine language routine
into the computer. Line 30 activates the printer. Line 40 reads the data
from line 80, which is a string of data defining a custom character (in
this case, the plus/minus character shown in the ImageWriter manual). It
is defined using eight bit data where all eight bits are required. Line 50
uses the custom character, and line 60 returns the output to the screen.
For more information on these procedures, see pages 69 and 70 of the
ImageWriter User's Manual, Part 1 (Apple Part #030-0730).