4 ms·

That's a nice emulator. Right now, one of the problem emulators struggle with is cycle accuracy. A (very) few demomakers (French Touch, Deater) are actually pus

by wiz21c 6y ago

That's a nice emulator. Right now, one of the problem emulators struggle with is cycle accuracy. A (very) few demomakers (French Touch, Deater) are actually pushing the boundaries on the Apple with cycle accurate timings for various video or sound effects and the emulators start showing their limits. However, for common usage (i.e. playing old games), emulators are perfectly fine. AppleWin seems the most advanced (lots of supported hardware, lots of small fixes to support edge cases of cycle accuracy), followed by Mame and Apple2JS. And some other I probably forget... Also, recently a new file format was introduced for better preserving the old floppy disk and their devious copy protection (WOZ). This will improve the emulators further (and already has as far as reading disk is concerned) Specific to the Apple2 emulation scene (I guess) is the effort of a person named "4am" to clean crack all Apple software so that they can continue working in the emulators (and old Apple's).

Narishma 6y ago
What does clean crack mean?
- sumtechguy 6y ago
  No scene intros, shout outs on startup, or extra payloads. Just a crack that makes the software work without some sort of '3rd word on page 2 8th paragraph from the manual' or only the original disk works because sector 22 is wonky or specific data. That plus the woz format which is a sector for sector copy (including extra wonky sectors). I think the most interesting one is the pinball construction kit which they only figured out a year or two ago. That one had many layers. MAME is also a good emu for Apple stuff if you want to try it too. The early mac stuff is a bit shaky due to a particular part not being emulated 100% yet.
  - joezydeco 6y ago
    WOZ isn't a sector copy, it's a raw magnetic flux copy with timing information added. It's extremely impressive stuff: https://wiki.reactivemicro.com/Applesauce https://wiki.reactivemicro.com/Applesauce It also makes really pretty images: https://twitter.com/a2_4am/status/1022567636914393088 https://twitter.com/a2_4am/status/1022567636914393088
    - sumtechguy 6y ago
      Thank you for the correction, I knew that but for some reason my brain spit out sector copy. Sorry about that. It is similar to what they are doing with LD and tapping pretty much right off the laser pickup. Woz is more of a filtered format after they toss out all of the extra junk doing a flux copy picks up. The LD guys are doing something similar. The pics are cool too because you can see how the devs were laying out the tracks and sectors to get a bit more perf out of the drives. I would have linked myself but this place I work does not let me at most of the emu sites.
      - joezydeco 6y ago
        The funny layouts were also driven by copy protection methods. The methods took advantage of physical properties of the disk and read circuit that the processor couldn't see but a duplication system could. The work by 4am and others was driven by the desire to preserve these works without needing to break the physical copy protection to do it.
        sumtechguy 6y ago
        The real annoying ones were the read the sectors in a block starting at 0 and going up you get one set of data. But if you run it backwards or do a deliberate seek you get a different set of data. Because of the interface or drive used or the firmware on that drive like you said. Starforce also used a variant of that. The super annoying ones are the ones that played with the ECC bits too or like the PS1 having a special wobble track. The laserdisc ones I am a bit excited for. They are getting some really nice images out of them vs copying it off the board in some random place or worse out of the svideo/RCA connector. Unlike the apple stuff they are having to resort to multi image copies to get an average of 'good' because of scratches or poor SNR out of some pickups. The apple ones can filter it to a point as you know you are supposed to get 8 bit chars out of it. With LD not so much though. Seeing the diff copy protections is kind of cool too like the ones where they put a special sector out of reach for normal firmware but they would re-write it on the fly and force the drive to read it. Think there were a few of those on the c64.
acomjean 6y ago
It alway cracked me up that some of the archived games I checked out had the same crack screens that I remember. I may have had a pirate problem in my middle school days. Are they still trying to clean crack games that they've imaged? The imaging of disks including their copy protection so emulation just works is pretty interesting. The data areas on disks are rather stunning. https://ia801001.us.archive.org/8/items/Antoine_Vignau_3.5_Floppies_Flux_May_2019_Batch/Dr%20Mario%20%28SOS%20Informatique%29/Dr%20Mario%20-%20Disk%201%20-%20Side%200.png https://ia801001.us.archive.org/8/items/Antoine_Vignau_3.5_F... ("Applesauce" creator/author twitter post gives summary of the applesauce disk reader, plus Ultima 1 was in Basic?) https://mobile.twitter.com/diskblitz/status/1258863201447366656 https://mobile.twitter.com/diskblitz/status/1258863201447366... The infrequent Apple time warp podcast interviewed the author: https://appletimewarp.libsyn.com/episode-6-applesauce-with-john-keoni-morris https://appletimewarp.libsyn.com/episode-6-applesauce-with-j...

by wiz21c 6y ago

Narishma 6y ago

What does clean crack mean?

sumtechguy 6y ago
No scene intros, shout outs on startup, or extra payloads. Just a crack that makes the software work without some sort of '3rd word on page 2 8th paragraph from the manual' or only the original disk works because sector 22 is wonky or specific data. That plus the woz format which is a sector for sector copy (including extra wonky sectors). I think the most interesting one is the pinball construction kit which they only figured out a year or two ago. That one had many layers. MAME is also a good emu for Apple stuff if you want to try it too. The early mac stuff is a bit shaky due to a particular part not being emulated 100% yet.
- joezydeco 6y ago
  WOZ isn't a sector copy, it's a raw magnetic flux copy with timing information added. It's extremely impressive stuff: https://wiki.reactivemicro.com/Applesauce https://wiki.reactivemicro.com/Applesauce It also makes really pretty images: https://twitter.com/a2_4am/status/1022567636914393088 https://twitter.com/a2_4am/status/1022567636914393088
  - sumtechguy 6y ago
    Thank you for the correction, I knew that but for some reason my brain spit out sector copy. Sorry about that. It is similar to what they are doing with LD and tapping pretty much right off the laser pickup. Woz is more of a filtered format after they toss out all of the extra junk doing a flux copy picks up. The LD guys are doing something similar. The pics are cool too because you can see how the devs were laying out the tracks and sectors to get a bit more perf out of the drives. I would have linked myself but this place I work does not let me at most of the emu sites.
    - joezydeco 6y ago
      The funny layouts were also driven by copy protection methods. The methods took advantage of physical properties of the disk and read circuit that the processor couldn't see but a duplication system could. The work by 4am and others was driven by the desire to preserve these works without needing to break the physical copy protection to do it.
      - sumtechguy 6y ago
        The real annoying ones were the read the sectors in a block starting at 0 and going up you get one set of data. But if you run it backwards or do a deliberate seek you get a different set of data. Because of the interface or drive used or the firmware on that drive like you said. Starforce also used a variant of that. The super annoying ones are the ones that played with the ECC bits too or like the PS1 having a special wobble track. The laserdisc ones I am a bit excited for. They are getting some really nice images out of them vs copying it off the board in some random place or worse out of the svideo/RCA connector. Unlike the apple stuff they are having to resort to multi image copies to get an average of 'good' because of scratches or poor SNR out of some pickups. The apple ones can filter it to a point as you know you are supposed to get 8 bit chars out of it. With LD not so much though. Seeing the diff copy protections is kind of cool too like the ones where they put a special sector out of reach for normal firmware but they would re-write it on the fly and force the drive to read it. Think there were a few of those on the c64.

acomjean 6y ago

It alway cracked me up that some of the archived games I checked out had the same crack screens that I remember. I may have had a pirate problem in my middle school days. Are they still trying to clean crack games that they've imaged? The imaging of disks including their copy protection so emulation just works is pretty interesting. The data areas on disks are rather stunning. https://ia801001.us.archive.org/8/items/Antoine_Vignau_3.5_Floppies_Flux_May_2019_Batch/Dr%20Mario%20%28SOS%20Informatique%29/Dr%20Mario%20-%20Disk%201%20-%20Side%200.png https://ia801001.us.archive.org/8/items/Antoine_Vignau_3.5_F... ("Applesauce" creator/author twitter post gives summary of the applesauce disk reader, plus Ultima 1 was in Basic?) https://mobile.twitter.com/diskblitz/status/1258863201447366656 https://mobile.twitter.com/diskblitz/status/1258863201447366... The infrequent Apple time warp podcast interviewed the author: https://appletimewarp.libsyn.com/episode-6-applesauce-with-john-keoni-morris https://appletimewarp.libsyn.com/episode-6-applesauce-with-j...