i´m new here and building up a site for SEGA Arcade boards and Games in my SEGA Network...
Since weeks i´m studying datasheets of CPU´s, Graphic Processors and general technical "facts" of all the SEGA arcade boards, which sometimes is hard work.
In relation to the Model 1 (and Model 2) board i´m a bit confused regarding the Fujitsu Co-Processor, which is presumably responsible for all the grahics work.
Some websites claim the SEGA Custom 315-5571, 315-5572 and 315-5573 chips are the Fujitsu MB86233 each. (in case of Model 2 there are more numbers like 315-5673, etc.)
Now i have two questions:
1. If each of the SEGA Custom chips contains a Fujitsu MB86xxx that would be 5 chips responsible for graphic functions on 1 board, is this possible?
2. On my research for the Fujitsu MB86233 i only found sites with infos on the chip, which are connected to the arcade/MAME community and no sites with technical documents or else.
But surfing in the old archived sites of Fujitsu Microelectronics with archive.org (http://web.archive.org/web/19970607073658/http://www.fujitsumicro.com/products/embctrl/embctrl.html) i found an embedded SPARClite Microprocessor called MB86933 (or his successor MB86933H), which IMO is the chip, which is used on the Model 1/2 boards.
Harmonizing this info with the infos from the official japanese SEGA Arcade History book, there are only two MB86933 with 20MHz each working on Model 1!?
Do you have any reliable informations about the true quantity and ID of the Fujitsu chips under the SEGA 315-xxxx caps?