pnakada@oracle.com (Paul Nakada) (03/27/90)
Well, that Apple ][+ emulator is really quite a novelty... it's so simple, it's a crime. Basically all it does is emulate a 6502, with all loads and stores to memory scanned for important locations. The include video memory and keyboard and speaker soft switches. The design allow for extremely easy customization and expansion. I have already added Language card support, with 128K Apple //c like banks not much more difficult. Before 128K though, I am going to bring up Prodos 8 on it. It should be very simple to intercept the Prodos device call and emulate a hard disk in the unix file system. Oh by the way, I added curses support, which (believe it or not) makes scrolling barely useable. It eases the bottleneck by updating the screen only after ~1000 machine cycles and then it update's the whole screen (not a character at a time) Like I said, though... It's really a novelty.. it's real slow on a sparc, but then again, it make's cross development and debugging a cinch on a sparc... anyone know of any debuggers for the Apple ][+? :-) it'd be a breeze to implement a single step/breakpoint debugger on the emulator... maybe this thing's got potential... enough rambling.. what do you all think about this "novelty"? -Paul Nakada pnakada@oracle.com
AKISUJAR@NUSVM.BITNET ("S. Sujarittanonta") (03/28/90)
RE: Paul Nakada Message on Apple II+ Emulator. Hello from Singapore, I just joined this discussion group but I am very musch interested in Emulating the Apple II on the newe computer system. I think P. Nakada idea is great. Perhaps he could elaborate it further. His message mentioned SPARC. Is it the SUN Sparc which using 68030 CPU? From what I know there are a few Apple II Emulators existed. One is 'II in a Mac' for Macintosh another is APPLE.TOS for Atari ST (both are 68000 machine) the first one is commercially available for $149.95, the later is PD program written by Darek Mahocka, Ontario, Canada. I have both programs but would like to see a newer development too. S. Sujarittanonta, School of Architecture, National University of Singapore. AKISUJAR@NUSVM.BITNET
chen@glycine.cs.unc.edu (Super Dave) (03/29/90)
In article <9003280155.AA11458@apple.com> AKISUJAR@NUSVM.BITNET ("S. Sujarittanonta") writes: >RE: Paul Nakada Message on Apple II+ Emulator. >Hello from Singapore, >I just joined this discussion group but I am very musch interested in Emulating >the Apple II on the newe computer system. I think P. Nakada idea is great. >Perhaps he could elaborate it further. His message mentioned SPARC. Is it the >SUN Sparc which using 68030 CPU? From what I know there are a few Apple II >S. Sujarittanonta, School of Architecture, National University of Singapore. >AKISUJAR@NUSVM.BITNET Actually, SPARC is Sun's own chip. It is a RISC chip based on the Berkeley RISC projects. The machine with the Sparch chip in is are sun 4's or Sparcstations (essentially the same thing). The Sun with the 68030 is the Sun 3/80. Typically the 3/80 is rated at 3 MIPs, while the sun 4's are 12-15 MIPs. Dave _________________________David_T._Chen_(chen@cs.unc.edu)_______________________ I tried to read ULYSSES when I was in college--I couldn't even understand the Cliff's Notes. -- Molly Dodd
news@medusa.informatik.uni-erlangen.de (News Administration) (03/29/90)
From article <PNAKADA.90Mar26235022@pnakada.oracle.com>, by pnakada@oracle.com (Paul Nakada): > Like I said, though... It's really a novelty.. it's real slow on a > sparc, but then again, it make's cross development and debugging a > cinch on a sparc... anyone know of any debuggers for the Apple ][+? > :-) it'd be a breeze to implement a single step/breakpoint debugger on > the emulator... > > enough rambling.. what do you all think about this "novelty"? Quite interesting. Of course to make it interesting, one has to do quite a few things too. Some ideas for improvement: - make many of the routines inline, and use gcc to compile, a cray will help too, for faster execution. - Output should really be generated for bitmap displays, so one could implement LORES, HIRES... - Disc i/o could be implemented by counting cycles in the interpreter, so one knows what to return, when someone accesses the DISC II I/O addresses. Using this scheme one could even run copy protected software from the emulator (hua, hua). Given the estimation of 0.3mips (for the 6502 at 1mhz, it should be possible to run the emulator at full speed on a >= 10mips machine (30 instructions should be enough to simulate one instruction). Seems that with a Sparc or 88k machine one can simulate an apple // rather good (A '040 would do too - Apple come one, make a full fleshed apple // emulator standard on your next series of Mac's !!). -- Toerless Eckert Internet: eckert@informatik.uni-erlangen.de X.400: /C=de/A=dbp/P=uni-erlangen/OU=informatik/S=eckert/
rhood@pro-gsplus.cts.com (Robert Hood) (03/30/90)
In-Reply-To: message from AKISUJAR@NUSVM.BITNET I find it interesting that this II+ emulator is being done on a Sparc, but for odd reasons. Nibble, one of the longest-lived Apple II magazines, used to be published by MicroSPARC, Inc. Recently they changed their name to MindCraft - because Sun offered them a good deal to change their name to avoid confusion with Sparc, as I recall! At any rate, ain't it interesting how this comes full-circle? Robert Hood - programmer ProLine address: pro-gsplus!rhood