6530 Programmer's Guide

Block Mode Operation
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6530 Programmer’s Guide
Set Video Prior Condition Register (Esc 7)
The Esc 7 sequence causes the 6530 to load the video prior condition
register with the attribute character specified. The attributes selected by
the Esc 7 attribute character are in effect for the entire screen, starting at
the beginning of the display memory, unless subsequent attribute
characters are encountered on the screen.
The Esc 7 attribute character does not take up a character position on the
screen. Thus, even though memory is cleared, these attributes remain in
effect. After a program reset, system reset, or mode switch, the prior
condition register is initialized to normal video.
Color Video
Attributes
For PCs with a color monitor and a color video display board, all the
video attributes are available except the underscore. How PC6530 maps
the underscore attribute depends on whether color mapping is selected.
(The user can set color mapping on or off with a PC6530 configuration
parameter.) When color mapping is off, the underscore attribute is
mapped to blue foreground characters.
When color mapping is on, PC6530 uses the bit pattern of the video
attribute character as an index to a color map table. The user can select
the colors used in the mapping scheme; otherwise, PC6530 uses default
colors. The user-selectable parameters associated with color mapping
are:
Color mapping. Specifies on or off. When on, PC6530 uses a
color table to map video attributes. When off, PC6530 uses a
monochrome table. (The default for color mapping is off.)
Normal intensity. Specifies high or low, which affects the actual
colors displayed on the screen. Users can select one of 8 colors, but
with the intensity setting, 16 colors are actually available in the
foreground (only 8 background colors are available). The dim
intensity attribute toggles the setting for this parameter. For
example, when this parameter is set to low, the dim attribute
switches it to high. (The default for normal intensity is high.)
Normal foreground color. Specifies one of 8 colors used to
display characters with the normal attribute. (The default normal
foreground color is white.)
Normal background color. Specifies one of 8 colors used to
display the background for the normal attribute. (The default normal
background color is blue.)
Underline foreground color. Specifies one of 8 colors used to
display characters with the underscore attribute. (The default
underline foreground color is brown.)