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From: iheitla@cs.vu.nl (Ilja Heitlager)
Newsgroups: comp.sys.amiga.emulations
Subject: CPU-emulators
Message-ID: <9587@star.cs.vu.nl>
Date: 8 Apr 91 13:51:25 GMT
Sender: news@cs.vu.nl
Lines: 34

I'm writing to this group 'cause (As far as I know) it's the only group for
emulations.
I'm planning to write a 6502 (and maybe when I like it some others) emulator.
I know that there are more of these emulators, but I want to do it myself.
I want to do it in C or Assembly. 

At this moment I think there are two ways of doing it:
	1- Compare every Opcode and jump to a routine which executes the
	   instruction
	2- Do it more or less the way the microcode does it.
	   Ok in software you can't do more operations at the same moment.
	
Questions:
	1- Is there any reaction on these ways.
	   (Or: I want to start a discussion)
	2- Are there any books about 6502, Z-80, 8088 microcoding.
	   or is this real TOP-SECRET.
	3- Are there any books about microcoding at all.
	4- Any ftp-sites which have sources-codes of CPU-emulators.
	5- How do you handle memory usage (For memory-mapped IO).

The only knowledge I have is A. Tanenbaum's book "Structered Computer Organisation", a apple II+ emulator and some diggin' in the 6502 (binary) opcodes
So any reply would be welcome.

BTW. Is there a newsgroup for CPU-emulator programming.

Ilja, 

        ====================================================                  
	Ilja Heitlager          | 
	Vrije Universiteit      | E-Mail <iheitla@cs.vu.nl>
	Amsterdam               |
	The NetherLands.	|            
        =====================================================