Same game on cassette 16 kb and on diskette 32kb?

[Serguei2]

I noted in Mobygames, some games on 8bit computers ask more memory on diskette than on cassette.

[zzip]

Because you need more memory to run DOS

 

Also they round up.   If a game says it requires 32K, it might not need the full 32K, but if it uses say 21K of memory, it's too big for a 16K machine so they round up to the next logical memory configuration.

 

EDIT:  there might also be game differences.

The Sierra On-line frogger is different on cassette than it is on disk.

Zaxxon drops a title screen from the cassette version that's present on disk (but I think everything else is the same)

Edited November 17, 2022 by zzip

[carlsson]

It depends on the computer too. While there was close to zero floppy disk based games for the VIC-20, in theory you could load it just as well from floppy disk on unexpanded machine as from tape. Actually with the random access of the disk, you probably could fit more into the game by segmented loading than what was practical from tape.

 

But yes, if a computer anyway required 32K RAM in order to even use a floppy drive, it was not much of an issue if the floppy disk based games also expected a computer with 32K. Only in the case that you somehow could attach the drive to a 16K machine and live with having even less free memory than when you use tapes, it would matter that certain games would not load on your machine.

[zzip]

17 minutes ago, carlsson said:

It depends on the computer too. While there was close to zero floppy disk based games for the VIC-20, in theory you could load it just as well from floppy disk on unexpanded machine as from tape. Actually with the random access of the disk, you probably could fit more into the game by segmented loading than what was practical from tape.

 

But yes, if a computer anyway required 32K RAM in order to even use a floppy drive, it was not much of an issue if the floppy disk based games also expected a computer with 32K. Only in the case that you somehow could attach the drive to a 16K machine and live with having even less free memory than when you use tapes, it would matter that certain games would not load on your machine.

When I had a 600XL, there was an idea that you couldn't run a floppy drive with only 16K RAM.   I don't know if that's strictly true, or it might have been that the Atari DOS menu which you needed to format floppies and other basic file operations couldn't run in 16K

 

I would assume that game developers could include the absolute bare-minimum disk I/O routines in their games that didn't consume too much memory and produce disk games that could run in 16K.   The Atari can read raw disk sectors without DOS, and that might be good enough to boot most games.   But I guess since Atari owners were advised to not use a floppy on 16K systems, then game developers didn't feel a need to try to squeeze disk games into 16K

[Krebizfan]

The opposite could occur thanks to disks making overlays easy and fast. The East German CP/M on cassette needed 256K of RAM to match what disk based CP/M could do with 64K. I haven't found any games that were designed for 48K with disk with a matching cassette version that needed a Spectrum 128 but it would not have been impossible. 

[Keatah]

In Apple II world you’d sometimes get additional features. And there always had to be room for DOS or some sort of loader and it’s associated copy protection routines.

[ClausB]

On 11/17/2022 at 4:46 PM, zzip said:

The Atari can read raw disk sectors without DOS, and that might be good enough to boot most games.

Yes, the OS ROM has a built-in loader for disk or cassette with identical formats, so any cassette-boot game which fit in 16K could also boot from disk into 16K. This wasn't done much in practice, though, because of copy protection.

 

The first game I cracked was Atari 400/800 Space Invaders on cassette in 1981. It used that boot format which was largely unknown at the time. It was documented in the OS technical reference which was not generally available then. My friend at the local dealer let me borrow his and I had it photocopied. I used that info to make a BASIC program to read the tape sectors and write out copies. Later when I got a disk drive I wrote the same sectors out to disk and got a bootable disk copy. But I was too cheap to use up a whole 90K disk on one 8K game, so I wrote a little menu loader and put several bootable games on one disk. These later included cart copies which could load directly into high RAM on a 48K system.