Specifications

Theory of Operation
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BIOS Flash EPROM
The main IBM-compatible BIOS and video BIOS resides in an Intel Flash device. It
is based on the Phoenix NuBIOS 4.04 code base. It includes the video BIOS,
supplied by Cirrus Logic, and support for flat panel displays. The BIOS supports a
set of six different flat panel displays. Refer to Appendix D for more information.
The Flash device has one 8KB parameter block is used to shadow the CMOS
memory, providing a method for saving setup information, even if the on-board
battery fails. The CMOS setup/restore can be done automatically by the BIOS from
the Exit Menu setups.
Super VGA / flat panel controller subsystem
A super VGA-compatible video and flat-panel display controller is provided on the
CPU board. The controller is implemented with a Cirrus Logic CL-GD7543
(“Viking”) part. The GD7543 includes an added MotionVideo and the following
features: GUI acceleration, multimedia acceleration and enhancement, standard
feature connector interface, 32-bit CPU interface, one 1 MByte of video memory,
support for 640x480 and 800x600 LCDs, simultaneous display on both CRT and flat
panel, 3.3V and 5.0V operation.
The VGA controller resides on the 32-bit 486 local bus. This requires the bus
interface section of the VGA chip to operate at 3.3V. All other sections of the chip
operate at 5V.
1 MB of video memory is present, implemented with two 256Kx16 DRAM devices.
This memory provides standard VGA modes on a CRT or flat panel display, up to
640x480 resolution in 16.8 million colors. It also provides super VGA modes up to
800x600 on flat panel displays, and CRT displays of 800x600 64K colors, and
1024x768 256 colors (non-interlaced).
The video memory is mapped to a region of the memory space above the maximum
32MB of system RAM.