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BigErn77
October 7th, 2012, 12:01 PM
So, I'm trying to play old DOS games (Space Quest, Castles, etc.) that I find online on my old Tandy 1000HX, and a major problem I'm having is that these games as downloaded have all their files lumped together in a folder, and I have no way of knowing which files go on which disks. I have no choice but to do it this way, that is, to copy the files to floppy disks, as the Tandy 1000HX has no hard drive.

Has anyone run into this problem and come up with a good idea on how to figure it out?

VileR
October 7th, 2012, 03:32 PM
Don't think there's a way that would work for *every* game... except for getting actual disk images instead of simple archives.

If you're comfortable with a debugger and a little bit of assembly language, you can debug the game running on another machine with a hard drive (or even in an emulator), set a breakpoint on INT 21h calls and see which files it's trying to open and when - that plus some intuition and guesswork could give you a good idea of which files have to be on which disk. The built-in- DOSBox debugger is a good one if you want to go that way.
A simpler approach is to open the executable in a hex editor/viewer, hunt for things that look like filenames, and see if they appear to be placed in distinct groups... which could correspond to different floppies. This may or may not be helpful, depending on how the game does things internally.

Or, just ask here - someone might have the original disks (or images thereof) to help you out.

I remember how ages ago I copied Golden Axe for a friend who had no hard drive - being an ignorant little kid I just blindly split it into two 360K floppies; he had to swap disks 12 times before each stage. :)

Great Hierophant
October 7th, 2012, 04:27 PM
Be grateful your machine uses 720KB floppies, they are usually easier to figure out compared with 360KB floppies.

DOSBox's debugger always alerts when programs are being open, no breakpoints required. I made several disk images with its assistance.

Stone
October 7th, 2012, 04:34 PM
I'm sure if you make a game by game list of the files and their sizes someone will be able to get you the information you need. I know that Maverick has just about every Sierra game. I'd bet all the games you have are well known here by somebody(s) and their disk composition can be resolved. So make that list and post it.

BigErn77
October 7th, 2012, 05:50 PM
Thanks, this is all excellent information. I think I will load up the game in DOSBox's debug mode. The game I got stuck on was Castles (Interplay, 1990). Some of the old Sierra adventure games were easier to guess about. I wonder if it is a common convention among these old multiple-disk based games to always prompt to "insert the correct disk" upon failure to find the needed file on the currently inserted disk (as opposed to having each disk's file lists "hard-coded" and hence failing when the file isn't found)?

(Sounds like Golden Axe is programmed that way.)

VileR
October 7th, 2012, 07:03 PM
DOSBox's debugger always alerts when programs are being open, no breakpoints required. I made several disk images with its assistance.

Correct - the breakpoints are just a matter of convenience (saves you the need to scroll back and find stuff). Can certainly do without them.

The only snag I can think of is with complex games that have a separate file for each sprite / character / animation / etc., and don't preload them on startup, so unless you play the whole thing all the way through you can never be sure - unless they're helpfully named (like "STAGE1.BIN", "STAGE2.BIN" and so on).


I wonder if it is a common convention among these old multiple-disk based games to always prompt to "insert the correct disk" upon failure to find the needed file on the currently inserted disk (as opposed to having each disk's file lists "hard-coded" and hence failing when the file isn't found)?

Wouldn't count on it, even among games from the same developer(s) - the only convention is "no convention". :)

Great Hierophant
October 7th, 2012, 07:23 PM
Correct - the breakpoints are just a matter of convenience (saves you the need to scroll back and find stuff). Can certainly do without them.

The only snag I can think of is with complex games that have a separate file for each sprite / character / animation / etc., and don't preload them on startup, so unless you play the whole thing all the way through you can never be sure - unless they're helpfully named (like "STAGE1.BIN", "STAGE2.BIN" and so on).



Wouldn't count on it, even among games from the same developer(s) - the only convention is "no convention". :)

Depends on the developer, Sierra was very consistent in its practices, but it used the SCI game engine for two dozen games.

DOSBox's debugger will tell you every time a program opens a file or the file it is trying to open. So start with a disk image of files you think the game is going to want, then play through and see which files it wants to find on the current disk and for which files it asks for a new disk.

Maverick1978
October 8th, 2012, 02:36 PM
..... or just ask around - via PM :)

Seriously... game archives and floppy images are not hard to come by, although they're certainly OT for this forum, insofar as directly asking "hey, anyone got some gamez for me!?"

hargle
October 8th, 2012, 03:41 PM
another option is put actually put a HDD in your tandy HX. I've got one in mine (via XTIDE) and there's not enough games out there to fill the drive up!

Maverick1978
October 9th, 2012, 05:37 AM
another option is put actually put a HDD in your tandy HX. I've got one in mine (via XTIDE) and there's not enough games out there to fill the drive up!
This is true - I have plans to do the same with my HX, but haven't quite gotten there yet!