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NFG Forums => Console Mods => Topic started by: Drewman21 on September 07, 2005, 12:15:41 PM

Title: Sega Genesis 68000 replacement
Post by: Drewman21 on September 07, 2005, 12:15:41 PM
I saw a site a long while back that taked about de-soldering the 68000 CPU from a original genesis and replacing it with a 68100 or a 68010 chip from older Apple computers.  Just wondering if anyone knows of this site or has any idea if this would work and where to look for said processor.  Thanks!

Drewman
Title: Sega Genesis 68000 replacement
Post by: Endymion on September 07, 2005, 04:19:26 PM
That would be Rob Ivy's page. He's a member here and it looks like you might have to try to contact him through his info here (search the member list) as his geocities-hosted site appears to be down.
Title: Sega Genesis 68000 replacement
Post by: hippy dave on September 07, 2005, 06:03:24 PM
i know the 68010 is definitely a drop-in replacement for the 68000, so would work fine. this i remember from the old amiga days. the amiga cpu was socketed tho, which would have been a bit easier ;)
where to get one? no clue, sorry...
Title: Sega Genesis 68000 replacement
Post by: Aidan on September 07, 2005, 06:30:36 PM
The 68010 isn't exactly much faster than the 68000 - at the same clock speed it'll struggle to manage much over 10% speed increase. You'd probably be able to overclock the existing 68000 in the machine by more than 10%!
Title: Sega Genesis 68000 replacement
Post by: Drewman21 on September 09, 2005, 12:32:48 AM
I've looked for Rob-ivy's website and i still haven't popped up a source for it.  Still would anyone know of a place that may sell the chip so i don't have to look for it in a installed piece of electronics.  My desoldering skills aren't bad but that many pins both ways is asking for trouble for me.   But other than that I know that you can do the over clock with the normal chip but from reading it it sounds like that you can loose synic between the sound and video. So if the 68010 was to be installed could the normal 68000 overclock be applied to that also?  Just a thought.  Anyone have any ideas?

Drewman21
Title: Sega Genesis 68000 replacement
Post by: Aidan on September 13, 2005, 06:47:29 AM
My understanding of the sound problem was that it was a timing issue between the 68000 and Z80 - something along the lines that the Z80 took a bit of time to get itself up and running and an overclocked 68000 would start shoving it instructions before it was ready to receive them. This seems to be critical when the system is starting up, but from what others have seen, it looks like it's less of a problem once things are up and running.

Swapping a 68000 and a 68010 wouldn't fix this problem. Yes, the same process is used to overclock at 68010 chip as a 68000.