Atari/C64 flippy disks

[lbaeza]

Hi

 

Some game titles were released on disk back in the day, with one side featuring the Atari version of the game, and on the other side, the C64 version of the same game. I think these were called "flippy" disks.

 

Datasoft's version of Pole Position has this feature, see the pictures of the disk.

 

Do you know any other titles like this?

Do we have a list of these games?

Kind regards,

 

Louis BQ

 

 

 

[Paul Westphal]

Lucasfilm disk games did the same. Koronis Rift, The Eidolon, Ballblazer, Rescue on Fractalus. Activision too.

[Rybags]

Pretty sure there was a disk of Elektraglide that was for both systems... that was how I got my initial copy.

[Heaven/TQA]

System 3 = International Karate

[carlsson]

Once I heard about disks with dual formats on the same side, but I don't know if that really works. I know the 1541 will seek for the directory + BAM at track 18, and then move the head in either direction depending on what the directory says files are located. I don't know how the Atari disk format(s) are designed, but I imagine one might be able to format only some tracks and as long as files and directory entries are kept inside that range, any two formats - possibly even a MFM and GCR side by side - could coexist.

 

Edit: The VTOC and directory on a 810 are stored in soft sectors 360-368 out of 720, which suggests to me it is in the middle of the physical disk area so possibly it would conflict with the 1541?

Edited March 11, 2016 by carlsson

[+DrVenkman]

My copy of F-15 Strike Eagle is a flippy disk. The Atari side still boots, last time I checked. Haven't ever tried the C64 side (don't have a drive cable for the Commodore).

 

 

Sent from my iPhone using Tapatalk

[Rybags]

For a multi format disk to work on Atari, you only need the track with the boot sector. All the others are optional.

Directory/Vtoc doesn't matter in most cases as the majority of games just use raw data without a file system structure.

I think 1050 actually by default will seek track 0 when you insert a new floppy or first turn the drive on. At that stage it does a density check which can be enquired by the Status command.

 

Not sure with C= disks though if it requires a Track zero to exist. Pretty sure their drives don't even seek when a new disk is inserted. No multiple densities to worry about so no reason for complex initialisation.

[MrFish]

Mercenary and On-Track

[lbaeza]

Lucasfilm disk games did the same. Koronis Rift, The Eidolon, Ballblazer, Rescue on Fractalus. Activision too.

 

Guys, thanks for your replies so far.

Paul, what Activision titles were released as flippy disk?

 

Kind regards,

 

Louis BQ

[Paul Westphal]

Master of the Lamps, and Great American Cross County Road Race

[R.Cade]

There are some with the game on the same side, either Apple+C64 or Atari+C64, but it's pretty rare.

 

Off the top of my head, some Mastertronic games are like this.

[+Allan]

http://www.atarimania.com/game-atari-400-800-xl-xe-chem-lab_1014.html

 

Allan

[luckybuck]

Synapse SynCalc 128K version

[lbaeza]

http://www.atarimania.com/game-atari-400-800-xl-xe-chem-lab_1014.html

 

Allan

 

Wow! Didn't know there were "educational flippy" also...cool...

 

 

Kind regards,

 

Louis BQ

[AtariGeezer]

Add Goonies to the flippy list too...

[R4ngerM4n]

Nearly all Mastertronic disc games.

[+CharlieChaplin]

Nearly all Mastertronic disc games.

 

Some of the Mastertronic disc-games were even multi-format and had both formats (e.g. C64 and A8) on one diskside !! Luckily all multi-format disks I had did not contain any copy-protection... and I always erased the evil C64 data on them...

 

Afaik, many Datasoft programs that fitted on one diskside (e.g. Bruce Lee, Pole Position, etc.) were flippies...

(Besides, all german "Europa" tapes were flippy tapes, C64 on one side, A8 on the other.)

Edited March 11, 2016 by CharlieChaplin

[Muzz73]

There was a game called "Ninja" that came that way, too. I had it back in the day with my C=64 (before I got my hands on my first A8).

[pixelmischief]

[DELETED]

Edited March 11, 2016 by pixelmischief

[high voltage]

I Got Chessmaster 2000 and Karateka on flippy.

and all Europa Computer Club tapes came on A8/C64 flippy tape

Edited March 11, 2016 by high voltage

[+Ripdubski]

 

Wow! Didn't know there were "educational flippy" also...cool...

 

 

Kind regards,

 

Louis BQ

 

 

And many productivity apps.

[lbaeza]

First Star Software's Spy vs Spy:

[Heaven/TQA]

@Andreas... How did the mastertronic disc format looked like? Aren't c64 format too different?

[lbaeza]

Mastertronic's Ninja

 

 

Hayden Software's Sargon III

 

Kind regards,

 

Louis BQ

[+CharlieChaplin]

@Andreas... How did the mastertronic disc format looked like? Aren't c64 format too different?

 

Well,

 

afair, a) the bootsectors and sectors thereafter did contain A8 data, b) followed by some empty sectors and then c) followed sectors that gave lots of read errors (contained lots of garbage, the C64 data, I guess)...

 

So I used a sector-copy program that would read a disk and continue on errors. When the disk was read completely, I wrote the copy onto the original disk (and the copy program wrote only the readable A8 data and it wrote empty sectors for all error sectors). Therefore I ended up with an original disk with just A8 data and without any copy-protection at all (and all my flippy-disks are already A8-only disks, since I copied the A8 data onto the other side as well).

 

At comp.sys.atari.8bit (which is completely dead nowadays!) at one point someone appeared and said that a) he knows how to get up to five different computer formats onto one diskette and b) he has the rights (or patent?) for these multi-computer-format disks...