Technical Information 1-23
Video Controller
The Tseng W32P PCI graphics controller is a PCI local bus video controller that delivers a
32-bit PCI-bus interface with the CPU. It features a graphic user interface (GUI)
accelerator, and advanced features for imaging and multimedia markets. Multimedia and
imaging are enhanced through the inclusion of an unique Image Memory Access (IMA)
port that allows direct access to the frame buffer at high speed. The IMA port allows
analog motion video to be converted to digital video signals. An 8-bit port into memory
allows images to be displayed on screen in real time, at color depths of up to 16.7 million
simultaneous.
Video Memory
There are eight 256k x 8, 45 ns DRAM chips soldered on the system board providing 2 MB
of video memory. The on-board video DRAM provides graphic support for 640 x 480 and
800 x 600 resolutions with 16.8 million colors, 1024 x 768 resolution with 256 colors, or
1280 x 1024 resolution with 16 colors.
EISA Bus
The system board uses the EISA bus for transferring data between the processor and I/O
peripherals and expansion boards. EISA connectors J22 through J25 allow installation of
both EISA and ISA expansion boards. The EISA architecture is fully downward
compatible with ISA hardware, and EISA boards, unlike ISA boards, require no jumper
settings. They are configured through software. A 6264LP 8K x 8 SRAM is used to
configure the EISA bus. This SRAM receives power from the bq4287 RTC, which uses a
lithium battery. Other EISA features include:
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32-bit memory addressing for the processor, DMA devices, and bus masters
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8-/16-/32-bit data transfers
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33 MB/sec burst mode data transfer
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Addressability up to 4 GB
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Efficient synchronous data transfer protocol for normal and high-speed transfers
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Automatic bus cycle translation between EISA and ISA masters and slaves
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Intelligent bus master peripheral controller support
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Enhanced DMA arbitration and transfer rates
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Shareable interrupts, programmable for edge or level triggering
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Automatic system configuration
The four EISA connectors contain two sets of contacts: one for EISA boards and one for
ISA boards. A tab prevents ISA boards from being inserted into the EISA contacts (see
Figure Section 1-3).