Dal wrote:I'm intrigued to know what the point was in applying copy protection to demos?
AtariZoll wrote:you can make 880K in regular format. More than it is possible, but only little - and using read track.
AtariZoll wrote:Dio, I really don't get why you write this. Many people used Hyperformat with success, and even some commercial games have such, 11 sect/track format.
troed wrote:Dal wrote:I'm intrigued to know what the point was in applying copy protection to demos?
Not copy protection - in the cases where the special format (not using FAT allows you to gain extra space) couldn't be copied with system or common copiers the demos themselves included a copying screen
I wrote it because I've looked at the spec.
Anything done at the duplicators I can certainly believe because read sector timing is more flexible than write, and since it's track-at-once written there aren't any write splices. Given that the PLLs should stay locked for the entire track, it's not out of the question you might even be able to eliminate all the 0s on the index PLL lockup and save a full 12 bytes there (although that might again require interleaving, and the CAPS FDC claims the FDC won't respond to a DAM closer than 28 bytes to the end of the index header so there's nothing to be saved on the data side).
Code: Select all
hyfil dc.b 11
dc.b 1,7,2,8,3,9,4,10,5,11,6 *sec No-s, interl. 6
*GAP-s for hyperformat
trleadh dc.w 3
Brume wrote:I didn't know the original was protected.
Dio wrote:However, you can build a completely legal 880K disk that can be read and written on the ST using 5 large and one normal sector per track (even with only 6190 raw bytes there's still more than 80 bytes per sector available). I'm surprised more commercial games didn't do this.
Thanks for answering. I guess you forgot after all this time, but no,
there are no single 6k sectors on Dragon Flight.
Track 0 is indeed standard and the rest are not. Tracks 1-79 have six
sectors, five 1k sectors plus one 512 bytes sectors. This gives you
5.5 Kb per track, exactly the same capacity as "standard" 11 sectors
per track, but your track layout is much more reliable. All 3 disks
have exactly the same format/layout except that the last one is
As a matter of fact, there is no such thing as a 6k sector on the ST.
The FDC doesn't support sectors bigger than 1k. It is possible to not
use sectors at all, and use a raw track with a capacity approx. of
6k. Some ST games use this format. But this is not very reliable, and
this is not the case on Dragon Flight anyway.
If you don't have original disks anymore, I can send you a Dragon
Flight's disk image with the copy protection and custom format
intact. It runs under the latest version of Steem perfectly well
exactly the same as the original (as with the original, you have to
create and use backup disks). You can use disk analysis tools to see
the track layout or you can even log and trace the disk reading and
copy protection. But you have the source, so I guess you should be
able to verify that you are reading 6 sectors per track.
Also, this custom format has no relation to the disk copy protection.
I mean, there is a disk copy protection on Dragon Flight that is
separated for the custom format. The custom track layout is not
actually a protection because most ST software copiers would handle
it without troubles. The protection is not in the sectors, is outside
the sectors. I'm not sure how much you want to talk about this, so
I'd prefer to avoid giving details without your authorization.
However, I consider that the most interesting aspect in Dragon's
Flight protection, is the one present in the "Backup disks". It is
exactly the same as in some famous ST copy protected demo. It is
a "seudo" protection because, obviously, the protection can be
created and copied in the ST itself. But the concept is quite unique
and brilliant. Hats off to you (or to Michael, or to whoever came
with the idea). Again, I'm intentionally avoiding being more specific.
AtariZoll wrote:Here is short part from my floppy format/copy SW:
Dio wrote:AtariZoll wrote:Here is short part from my floppy format/copy SW:
Thanks for that, very interesting. Can you tell me what each of the GAP sizes is used for?
I have KF image of The Union Demo that MugUk sent me, as he was kind enough to dump it one year ago when I was working on IPF support for Hatari.
Brume wrote:- The Overscan Demos by Paulo Simoes. If i remember correctly, it was hacked by Paulo Simoes in order to make a .ST/.MSA file
AtariZoll wrote:There is contradiction. What can be imaged as MSA or ST is not considered copy-protected. There is a lot of SW what can put them in image, and write onto floppy, reproducing 100% working copy. No FAT, no visible files ? It will not prevent hackers to steal code.
Extra space may be the reason, but you can make 880K in regular format. More than it is possible, but only little - and using read track. I really would like to see some demo with it
Since Ijor has Union demo on his Pasti site, it must have some real copy protection.
Users browsing this forum: No registered users and 12 guests