Modes
of
Operation
The IBM Monochrome Display and Printer Adapter supports 256
character codes.
In
the character set are alphanumerics and block
graphics.
Each
character in the display buffer has a corresponding
character attribute. The character code must be an even address and the
attribute code must be an odd address in the display buffer.
,.............,
7
6 5 4
3 2
o
CHARACTER
CODE
EVEN
ADDRESS
(M)
7
6 5
4
3
2
0
ATTRIBUTE
CODE
BL
R I
R B
I
G
I
B
I
G
ODD
ADDRESS
(M+l)
I
I
I
..
FOREGROUND
~
:
INTENSITY
BACKGROUND
~
...
BLINK
The adapter decodes the character attribute byte as defined above. The
,.............,
BLINK
and
INTENSITY
bits may be combined with the
FORE-
GROUND
and
BACKGROUND
bits to further enhance the char-
acter attribute functions listed below.
BACKGROUND
FOREGROUND
FUNCTION
R G B R G B
0
0 0
0
0
0
NON
DISPLAY
0 0
0 0
0 1
UNDERLINE
0 0 0
1 1
1
WHITE
CHARACTER/
BLACK
BACKGROUND
1 1
1
000
REVERSE
VIDEO
2-40