[sdiy] D7811G

[Rainer Buchty]

> Has anyone seen a datasheet for the NEC D7811G?  I think its an 8080
> compatible CPU.  Used in the Juno106 and the current object of my
> torturous intentions, the Akai MS20A.

And I was about to ask if you were hacking the Casio CZ synthesizers...

Problem with that beast is that you really need to convince it the hard
way to reveal its ROM contents. As long as the program never accesses an
external, additional ROM there's hardly a chance that you can read out its
contents. But if the program jumps anywhere above 0x0fff you're set --
just place your own ROM-readout routine there.

You can get the datasheet from
	http://wwwbode.cs.tum.edu/~buchty/upd7811g.pfg

Note that it's the datasheet for the development version with a
piggybacked ROM.

> Before I go through the major hassle of convincing NEC that they made this
> thing that indeed they are still used and that they would gain much Karma
> by photocopying the datasheets, I figured I'd ask...

Actually, I got my copy from Partminer. They tend to hide away more and
more datasheets, but from time to time you still can download an old one
for free.

Rainer