Emulator support for Atari APE/ProSystem question

[atx4us]

Hello,

 

I've purchased the excellent APE/ProSystem software and I can now backup my favorite protected disks. The drawback is that I can only use the ProSystem disk images on real Atari hardware. This is not good for me because I don't know how much longer my Atari hardware will hold out. Does anyone know of any Atari computer emulators out there that can "properly" support the ProSystem disk images? This is the top item on my emulator wish list!

 

Thanks

[atx4us]

I guess I can ask the question in another way. Is there a good reason why the top emulators haven't supported the ProSystem disk images? This would be a great feature, right?

[atarimac]

Actually, yes, there is a very good reason. The PRO disk format has not been made public, so it's hard for emulator authors to incorporate it. I suspect the reason the PRO format is not public is due to the business model there. It's not in the authors interest to see more emulation in use than real hardware, as that would decrease his hardware sales. The fact that the PRO format is not public is why the VAPI/ATX format was created, but it suffers from some of the same issues. The format is now public, but some of the timing calculations and how the format is used are hidden in the DLL, who's source is not available.

 

People are trying to work around both of these issues by reverse engineering. The author of Altirra has added support for both formats to his emulator, and Atari 800 has the PRO format in the latest CVS code. On both of these, they probably cannot guarantee 100% support do to doing it by reverse engineering. On Windows platforms, there is a version of Atari800WinPuls which uses the DLL to load VAPI images. For Linux and Mac, I'm about to check in a version of code that can load 80-90% of the VAPI images.

[classics]

ProSystem works well for what it was intended for when it was created 14 years ago. It was never intended for emulation, since except for PC-Xformer, there were no emulators then, and PC-Xformer didn't even support SIO2PC ATR images, much less run anything worth backing up.

 

ProSystem also makes 'lossy' copies of disks because it uses un-enhanced drives, as it was intended to do, Happy drives and upgrades were actually still hard to come by at the time, so it does not capture all the information needed to actually emulate a spinning disk.

 

VAPI on the other hand is very much suited to emulation since it uses enhanced hardware to read all the information you can't see with a unmodified disk drive. If you are concerned with archival and/or computer emulation, VAPI is a much better choice than ProSystem for storing your images.

 

APE fully supports VAPI images as well, for both RS232 and USB adapters. Just put the VAPI DLL in the APE installation directory and restart APE to enable loading of ATX images.

 

Steve