Sega Virtua Processor
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The Sega Virtua Processor (short: SVP) is a DSP introduced by Sega in 1994 to expand the Sega Mega Drive's (Sega Genesis in North America) 3D capabilities.
The SVP was Sega's answer to Nintendo's Super FX processor used in some of their SNES cartridges.
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[edit] Technical Details
The SVP is a Samsung SSP1601 with Sega branding but was assumed to be a SH-x DSP for a long time in the homebrew scene. The assumption was based on the fact that Sega has used SH-1 and SH-2 processors for their 32X and Saturn consoles.
The first, and only usage of the SVP was in the Sega Mega Drive/Sega Genesis version of Virtua Racing. Its main task was to calculate the vector graphics of the game. The main purpose of the SVP is to render polygons as 8x8 patterns, which the game program transfers to VRAM from the 128K RAM area using DMA.[1]
[edit] Implementations
At the time of release, the SVP was set to rise the cost of the Virtua Racing cartridges (the game cost £70 in the UK, and $100 in the U.S.), which can be seen as a major reason why the SVP was only used in Virtua Racing. Sega of America started to develop the 32X expansion console around that time.
Due to the SVP, Virtua Racing is the only Mega Drive game which doesn't run with an attached 32X. A 32X version of the game called Virtua Racing Deluxe was released later in 1994, featuring more polygons per track and car, three cars and two more tracks. It has been theorized by many that a SVP adaptor (similar to the 32X) was in development prior to the 32X creation.