Denise C64 mode problems!

[PiCiJi]

Originally Posted by amilo3438

chessmaster_2100_s1[software_toolworks_1988](patched) ... It already exists, if we can assume that the patched version was manually edited in the same way! (tested to work in denise)

Improbable. Copy protections with variable bit cell density on same track should simply not be used with a G64 or, in the case of the Amiga, ext. ADF. For this purpose, a flow change format should be taken. If not, it's technically a hack to handle the copy protection, similar to a D64 or ADF.

Originally Posted by amilo3438

But not everything is so simple! We learned something from all this, and that is that there are situations when we suspect that the g64 is faulty, but it just needs some specificity in the settings, eg a different version of the disk drive, or in the start command (":*" instead of "*" ), or it needs to be started by entering the file name because it is not at the beginning of the disk, or TV standard (PAL or NTSC), that could have an effect on making it work.

The problem is, you don't know if a G64 is okay just because it works with 1541, but not with 1541-II.
It is more likely that the G64 is not completely clean. Slight deviations, such as different firmware (1541, 1541C, 1541-II) or disk wobble, should not be enough to cause a problem.

Originally Posted by amilo3438

In fact, the focus now seems to be on finding something that would work on one of the other emulators and not on denise! (to make collection of examples)

yes that would help to draw some conclusions.

Originally Posted by amilo3438

Any idea if Denise is having trouble with any of the more complex protections?

VMAX should be working.
oscillation (weak bits) should be working.
Honestly, with formats like IPF or P64, nothing special needs to be emulated to handle all copy protections.
Unfortunately, no group has set itself the task of mapping C64 originals as P64 (IPF).

[r.cade]

Actually, a G64 track can contain multiple densities. It's just that no emulators (that I know of) support that, and it must be manually constructed anyway.

[PiCiJi]

Originally Posted by r.cade

Actually, a G64 track can contain multiple densities. It's just that no emulators (that I know of) support that, and it must be manually constructed anyway.

That's right, that's what the specification provides. I haven't thought about that for years. At that time I could not find a G64 that provides data for this. Are there any ?

The effort to emulate this information with a G64 is quite large.
The P64 is much better suited for this.