Z80 Emulation

[bloodline]

Sorry, since I don't know much about the Z80. But as far as I know, the Z80 is 8086 compatible... does this mean that one could run Z80 software (like a Spectrum Rom) on an Athlon/P4 in real mode?

[xeron]

bloodline wrote:
Sorry, since I don't know much about the Z80. But as far as I know, the Z80 is 8086 compatible...

Not true. The Z80 is a not 100% clone of the 8080, which was then upgraded along its own seperate path (Z180/HD64180). You could modify the spectrum ROM to 8086 code, but why?

[chris]

The Z80 was created by people who worked on the 8086 (or maybe an earlier one, can't remember now), but it was never designed to be compatible AFAIK.  I very much doubt you could run Z80 software on a P4, and the Spectrum ROM's absolute memory addresses would likely cause problems (not to mention that it corrupts itself if it isn't write protected)

Chris

[bloodline]

xeron wrote:

bloodline wrote:
Sorry, since I don't know much about the Z80. But as far as I know, the Z80 is 8086 compatible...

Not true. The Z80 is a not 100% clone of the 8080, which was then upgraded along its own seperate path (Z180/HD64180). You could modify the spectrum ROM to 8086 code, but why?

I have have an (un)healthy obession with Emulation for some reason at this time. I was just wondering about things like that...

[xeron]

I have had a long obsession with emulators. I have on my system an unfinished emulator for a non-existant computer. I designed a 6502 based computer, wrote the beginnings of an emulator (not all the display modes and sprites I wanted to add yet, but enough to get text on the screen and read the keyboard), then started writing a BASIC interpreter for it in 6502 asm. It actually got quite far (you can write simple BASIC programs in it).

Also, I have an unfinished Arcadia 2001 emulator written in 68020 assembly. Thats pretty cool. You can just about play the "3d" bowling game in it. Most games show bugs, though :-(

Before that I wrote a games console emulator for a non-existant games console (spot the theme ;-) ). I wrote a tron lightcycles game, a space invaders game, and most of a boulderdash engine for that.

I've never released any of this, although some of my friends have seen them. They were all just for fun, anyway.

[bloodline]

Yes, I see exactly where you are comming from. I have spend many an hour making Emulators for CPU's that I have just drempt up. That is the best way to learn how CPU's work and why designers make the design decisions they do!!!