From: utzoo!decvax!ucbvax!C70:info-cpm Newsgroups: fa.info-cpm Title: Re: A z-80 emulator for the 8080/z80 Article-I.D.: ucb.1530 Posted: Fri Jul 16 14:22:26 1982 Received: Sat Jul 17 02:50:15 1982 >From rconn@BRL Fri Jul 16 14:22:14 1982 Eliot, First of all, do you want an EMULATOR or a SIMULATOR? To me, Emulation implies changing the microcode of one processor to make it look like another. The VAX 11/780, for instance, has a PDP 11/70 emulation mode, in which case the User MicroControl- Store is programmed to recognize PDP 11/70 machine code. If you want a simulator, that's basically what DDT, SID, ZDT, and ZSID are. They simulate execution of machine code by a processor and allow you to watch what happens while the code runs. You can watch registers change and even examine what hap- pens to memory between each instruction. The EM8080 program you mention is what I would call a simulator. Note: You HAVE to have a microprogrammable machine in order to perform emulation. The AMD2900 bit-slice chips would be an example. There are several GP-machines, such as the GenRad 2900 (number correct?) and the Tektronix 85xx-series. They pro- vide cross-software capability like what you are probably looking for, but they are probably outside the price range you are in. I have not seen any public-domain simulator for a Z80 which runs on an 8080 ... ZDT and ZSID both run on a Z80 for a Z80 and are rather complete simulations. Rick