14 lines
678 B
Plaintext
14 lines
678 B
Plaintext
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The SGI Visual Workstations (models 320 and 540) are based around
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the Cobalt, Lithium, and Arsenic ASICs. The Cobalt ASIC is the
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main system ASIC which interfaces the 1-4 IA32 cpus, the memory
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system, and the I/O system in the Lithium ASIC. The Cobalt ASIC
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also contains the 3D gfx rendering engine which renders to main
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system memory -- part of which is used as the frame buffer which
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is DMA'ed to a video connector using the Arsenic ASIC. A PIIX4
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chip and NS87307 are used to provide legacy device support (IDE,
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serial, floppy, and parallel).
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The Visual Workstation chipset largely conforms to the PC architecture
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with some notable exceptions such as interrupt handling.
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