I've just release a little command-line tool that allows to convert .DMK disk images to SuperCard Pro .SCP format. The generated .SCP files can then be written back to a real floppy disk, assuming of course you own a SuperCard Pro device. DMK2SCP can be downloaded from my website. Sources are also available and can be easily recompiled for other platforms (that's very standard C).
I wrote back several DMK files to real floppies this way, it worked fine for all of them, except for Ys II, which was working, but only on the Sony HB-G900AP. On turboR, the demo of the game does not even launch. On VG8235, the demo works, but the game is stuck on a black screen after pressing space (no moving drive heads sounds from the drive). On HB-F1XDJ, demo works too, game is also stuck on black screen after pressing space, but the drive heads keep moving back and forth forever.
Here's the log of the conversion process by DMK2SCP:
Here's the bitcell timing vizualization of the original track 144:
A SuperCard Pro device stores the timings for each bitcell on 16 bits. You can see here that this track has 11 sectors by counting the different separated clouds of points.
And here's the bitcell timing vizualization of the track 144 generated from the DMK file:
A .SCP file generated from DMK is only using a set of 3 different exact values, which are not floating around a median value, that's why you see lines here, and not a could of points. But you can still see that there are 11 parts here.
My explanation so far is that those small timing differences are not handled the same way on all MSX machines. Also, I fogot to mention that the DMK file used to generate the SCP file is working on openMSX.
An attempt of fix would be to add some artificial randomness in the bitcell timings when generating the SCP file (in order to recreate the "cloud of points" aspect). I tried that with different parameters but with no success yet.
As an additionnal note, here's what a standard track formatted on VG-8235 looks like:
It appears clearly that the timings are not as widely spread as for Ys II. So maybe that's part of the protection mechanism.
