Chapter 3 – Installation
3-19
filled by the 640 x 400 resolution of this particular mode. By enabling the expansion
function, these lower resolutions will better utilize the display by stretching the informa-
tion in an attempt to fill the display. Operating systems such as Microsoft Windows 3.X,
Windows 95, and Windows NT use display drivers to handle the different flat panel dis-
plays. Here expansion is not necessary since there is a specific driver for each resolution
display.
Expansion does not add any resolution to the existing information; it simply stretches the
information to better fit the display. Text and graphic screens can look somewhat grainy
from the process of expansion. If the effect of expansion is undesirable, it can be turned
off either in the BIOS setup, or by executing an included utility program. See the table
below for the three utility programs included to allow expansion to be turned on, turned
off, and set back to the BIOS default state and what effect they have on the display.
Video Expansion Options
Utility
Mode
Panel Type/Size
12.1” STN
12.1” TFT
EXP_ON.EXE
Text
Vert/Hor
Vert/Hor
Expansion On
Graphics
Vert/Hor
Vert/Hor
EXP_DEF.EXE
Text
Off
Vert/Hor
Expansion Default
Graphics
Off
Off
EXP_OFF.EXE
Text
Off
Vert/Hor*
Expansion Off
Graphics
Off
Off
Definitions:
Vert - Vertical only expansion is invoked
Vert/Hor - Vertical and Horizontal expansion is invoked
Expansion Default - The video BIOS default on power up
* Text expansion cannot be turned off
With a 800 x 600 display, the stretching algorithm does not completely fill the display
horizontally or vertically. A greater vertical text expansion can be achieved by changing
to VGA mode 3* (see Note below). This is also an 80 column, 25 row text mode but with
an effective resolution of 640 x 350. The 350 lines stretch better to fill the 768 line dis-
play than does the default DOS mode 3+.
Note
The utility disk includes a program titled
MOD3_350.EXE
,
to allow
switching to the VGA mode 3*. Another utility program,
MOD3_400.EXE, is provided to put the mode back to the DOS default
of 3+.
