> > The Final Lap schematics suggest C139 is a full-fledged ASIC or else some really > > offbeat DSP (host data is 13 bits wide). The signal names used there suggest that > > it's implementing something approximating a token ring protocol. The chip has > Fujitsu > > markings, which is not a good sign. > > I'm pretty sure it's used for player board comms on Galaxian 3 too btw, which has *9* > of them on one of the PCBs. > > If we do start to see progress with the Laserdisc stuff that's definitely going to be > an issue (although it's not even 100% sure due to the hardware, even without 2 > laserdiscs running in sync and having to be decoded at the same time)
Nine C139 controllers? I can't imagine how that is going to work. I honestly didn't request Galaxian 3 hardware progress because how large of a setup that is.
Someone should explain how Fujitsu chips are a bad sign in Mame? This looks like to me these chips are very well designed. It's no surprise Sega used these chips on their comm boards before Sega Model 3. There is also the GMEN pcb that uses a Fujitsu firewire controller for cabinet linking as opposed to the C139.