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stephancom

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About stephancom

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    Combat Commando
  1. It’s online somewhere but I have (somewhere) a physical paper copy I bought on eBay, I’ll scan it if I can’t find it elsewhere. Cheat code I think is either *#* or #*# followed by a level number?
  2. haha and I’m referring to something more than thirty years ago! I don’t doubt for a second that my modifications slowed it down noticeably. That long jump happened all the time, surely several times per game loop, and it’s not like we had some fancy interrupt driven draw routine decoupled from the play loop like you would have today. Though it does give me an insane urge to go back and see if I can improve it. There is no way that would be productive use of my time.
  3. Ell oh ell. Probably they were thinking you could disassemble it and do a diff. Which would lack comments and just not be the same. Plus, if I know my habits, I probably had made backups at multiple points in development. Maybe not, floppies were expensive, and it was huge, took forever to assemble, but odds are there’s copies comprising snapshots at most two weeks apart. I wish I’d had git then, or at least CVS. But I never heard of source control for another decade - or unit testing for another decade after that.
  4. Oh!!! That might have been what I had to do to free up memory! I took out a level! I bet that’s it! The original code was a solid 16k, I had to do something to make room for the bank switching and cheat mode. I bet I dropped one of the levels, that would be the easiest thing, nothing else was “optional” As for performance, this part I remember clearly, I had to split it up into two banks, so any long jump (BLWP? Maybe? Been forever since I did 9900. Maybe without the workspace pointer?) went through a routine that was in the same place in both banks. I checked the high bit to tell if you had to switch, and switching took time, I think I even had a string of NOPs or something to kill time waiting for the switch? And then you’d land in the other bank and get routed to where you needed to go. I thought of it at the time as a bit like the bridge in Back to the Future III, I had to make sure the track would be there on the other side so the back switching routine was the same code in the same spot on both sides, I think at >7000, the only difference is one would switch if it was heading to an address in the >8000 range (and flip that bit), the other if the destination was in the >7000 bank (and not flip the bit, but flip it if we’re NOT bank switching) it might have been at the end of the bank, like >7F00 or something, because I bet >7000 probably had to be initialization code and/or interrupt handling? could it have been better? could I maybe have only done the switch if the destination needed it? Maybe, or maybe I did do that, or maybe it wasn’t practical... I’m a real good programmer, and I was really good then, so I bet I did ok. I might have moved some subroutines around to avoid switching? Bank switching and cheat mode were requirements handed to me, not my decision, hardware constraints for the former, I think the latter was mainly for QA. Maybe if I had a few more months to dick around I could have shaved a few bytes here and there instead of dropping the level but my memory is that the code was REALLY tight to start with. If it wasn’t, I bet the other guy would have added another level, he was out of space, and in general (to my memory) all or nearly all of the code was needed on every level.
  5. To recreate what? The source code, or the commits? Either way, no, I don't expect anyone could do it - you'd be missing something essential - the comments. I don't remember the comments being particularly extensive, but there were some, and there is no way you could recreate them.
  6. You are correct. I am the Stephan Meyers mentioned in the splash screen. I was hired to prep it for sale as a cartridge - DBI handed me 16kb of more or less complete code, my job was to: * break it up to run in 2x 8kb ROM banks * change the name and graphics * write the manual * add the cheat code ... maybe some other things? Like I think I had to refactor a little to shave off a few hundred bytes? I was a teenager, it's my first published work, I don't really remember. It's otherwise nearly identical. I might have some floppy disks in a storage space in Texas containing the source code. I may go there next year. If I do have that, I would possibly have the original source code from before I changed it around. If they're readable, and someone can give me the files, I would be willing to put them up on my GitHub - reconstructing, if I can, commits that would show the difference. I suppose in theory that would be a violation of some copyright or something I signed 35 years ago, but I can't imagine who would go to the trouble of enforcing it. More likely, they're gone, or they're unreadable. If anyone has other questions, I can try to dredge up answers, but again, it was a very long time ago.
  7. I'm the "stephan meyers" mentioned in the splash screen - I was handed the more or less completed game, 16kb of code, and tasked with making it run in 2x 8kb banks, writing the manual, changing the graphics (it was originally "jumpman") and otherwise prepping it for release. I might, maaaaaaybe have some floppy disks in a storage space in texas with the source code. Wouldn't bet on it. Might pick it up next year.
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