@8FDB.ADF - IBM
XGA Display Adapter/A
Init file for @8FDB.ADF
XGA Adapter /A 75X5887
J5 Pads for
20 pin header
U7 TDK ZJY-2P
U8 TDK ZJY-2P
U9 TDK ZJY-2P
U11 Toshiba TC110GC9A6
U20 OKI M51257AL-12
U34-U41 Video RAM
U44 40.0000 MHz
U45 44.9000 MHz
U46 28.3220 MHz
U47 41.5390 MHz
U48 25.1750 MHz
U34-U41 Toshiba TC524256BZ-10 or
This card shares the same video chipset as the 9590 planar.
J5 Function It looks like a header
to supply a video accelerator card that lacks an AVE connector with base
Finally beat them out of Peter 2 Jun 00
U44 40.0000 MHz DMA Clock
U45 44.9000 MHz Pixelclock
1024x768, 43.5Hz I (8514/A) mode
U46 28.3220 MHz VGA / Text
U47 41.5390 MHz Pixelclock
U48 25.1750 MHz Pixelclock
640 x 480 / 400 modes
Videoram 1024 (Easy, it's either 512 or 1024)
Clocks 28.322 25.175 41.539 44.9
The XGA card is an entire graphics subsystem that does
not have to rely on a video subsystem on the motherboard of the machine
where it is installed. The XGA card is a Bus Master, which means it can
do its own processing and memory accesses without having to use the main
system processor, providing faster video processing and freeing up the
main processor for other tasks.
The drivers and the card itself have been optimized to
work with the 386 32-bit instruction set. The XGA card comes standard with
512KB of VRAM which provides a maximum resolution of 1024 x 768 with 16
colors. If the memory is upgraded to a full 1MB the maximum increases to
1024 x 768 with 256 colors.
The XGA Adapter was upgradeable to 640 x 480 with 65,536
colors (!) and 1024 x 768 with 256
colors by means of the PS/2 Video Memory Expansion Option.
On IBM PS/2 computers with a 16-bit bus, and XGA, the following
error message may appear after installing the XGA drivers in Microsoft
The aperture enabled for the xga
device is invalid, please enable the 4MB aperture (preferred) or 1MB aperture
using the xga reference disk.
This error occurs on 16 MB 16-bit bus PS/2 computers that support
a maximum of 16 MB of RAM, such as the model 9556 or 9557.
The PS/2 XGA subsystem provides three possible apertures, or
windows, to video memory in the physical memory address space of the system.
Aperture size options are 64KB, 1MB, and 4MB. The 4MB aperture option is
not available on 16-bit computers, such as those based on the 80386 SX
processor. The 4MB Aperture is not available if the XGA subsystem is in
a 16 bit slot in a 32 bit computer and is only accessible by 32 bit protected
mode drivers, such as the drivers used by Microsoft Windows NT.
Currently, Microsoft Windows NT only supports XGA with an Aperture
of 1MB, or 4MB enabled. On 16-bit IBM PS/2 computers with 16MB RAM, the
1MB meg aperture cannot be enabled.
According to IBM , a possible workaround is to use the standard
VGA which does not require this option to work, or decrease the amount
of physical RAM below 16MB.
XGA Display Adapter/A
Video I/O Address
I/O (Input/Output) address range for the display controller
registers. This field also affects the location of the video coprocessor
registers. Each adapter you install must have a unique address range.
<"Instance 6: 2160h - 216Fh">,
1 (2110-211F), 2 (2120-212F), 3 (2130 - 213F), 4 (2140- 214F), 5 (2150-215F),
7 (2170-217F), 0 (2100-210F)
1 MB VRAM Aperture Base Address
1 MB aperture from the PC into the video memory. If the
aperture has been disabled, it is because there wasn't enough available
memory address space for system memory and the aperture.
If the aperture must be re-enabled, and if you cannot use "Set
Configuration", then remove the device that is competing for memory such
as a system Micro Channel adapter or system memory.
Removal of system memory may degrade the system performance.
If the aperture has been allocated an address range and it results in a
reduction of usable system memory (with Micro Channel memory adapter)
then the aperture can be disabled.
(Ed. On most systems with >16MB,
disable the aperture)
<"Address at 15 MB (F00000h)"
(0F000-0Ffff)>, 14 MB (0E00-0Efff), 13 MB (0D000-0Dfff), 12 MB (0C000-0Cfff),
11 MB (0B000-0Bfff), 10 MB (0A000-0Afff), 9 MB (9000-9ffff), 8 MB (8000-8fff),
Video Arbitration Level
Arbitration level the adapter uses to transfer data.
<"Arbitration level 13">,
12, 11, 10, 9, 8, 14, 7
Select the Bus Arbitration Fairness. When Bus Arbitration
Fairness is set it controls whether the adapter will release control of
the bus when it has been using it exclusively.
<"Fairness On">, Fairness
ADPItem 1 ROM Address Range
This field shows the address of the 8K block of memory
that is assigned to the adapter. Only one XGA or XGA-2 Display Adapter
will have the ROM assigned, and any other XGA or XGA-2 Adapter installed
will share that address range.
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