Prince of Persia isn’t just a recent movie. It’s based on a video game series, the first of which was first released all the way back in 1989 for the venerable Apple II series of 8-bit computers. That original game, extremely simple by today’s standards, is a classic today.
The author, Jordan Mechner, had given up on looking for the 6502 assembly language source code behind the game until his dad found a box of disks buried in a closet. Among them were several hand-labeled disks claiming to contain the long-lost code.
Mr. Mechner equates it to discovering the original sheet music to something that’s already been recorded. Another musician can reconstruct the music by listening to it, but certain subtleties will always be lost in that process. In music, you can get by with some of the guesses being wrong, or just plain improvisation, and you can just call it artistic license. Computers are more sensitive to artistic license.
A hobbyist ported Prince of Persia to the Commodore 64, using memory dumps of the original Apple II game, but there were things that didn’t work right–an example of artistic license striking. Now that the source code is available, it will be easier to fix it.
Wired has a nice account of what happened the day Mr. Mechner, aided by archivists Tony Diaz and Jason Scott, recovered the original source code. It also reveals some of the other things, lost for decades, that they turned up–including some software that for various reasons was never released.
With the source code recovered and now released for all comers to examine, the glitches in that Commodore 64 port should be much easier to fix. And if someone wants to port the game to other 1980s 6502-based computers like the Atari 800 series, that job will be much easier.
And if you want to avoid having to attempt your own digital reconstruction of your stuff, Mr. Mechner has the following advice to relay from Mr. Scott:
If you have data you want to keep for posterity, follow the Russian doll approach. Back up your old 20GB hard drives into a folder on your new 200GB hard drive. Next year, back up your 200GB hard drive into a folder on your new 1TB hard drive. And so on into the future.
If there’s anything I disagree with there, it’s only storing the data on hard drives. I’d plan on buying a USB flash drive every few years and storing the data there, too. When you retire your HDDs, copy their contents onto USB flash drives when you upgrade to a new hard drive, and store the old drive(s) and USB drive(s) someplace safe–a closet in your house’s living space, ideally. Then repeat the process as you buy new drives. Flash media is likely to have more longevity when just sitting on a shelf, but two copies on two forms of media in the closet, plus the copy on your PC gives you several chances to preserve your old data.