Copying Protected Disks

[Tech]

I have 5 original C64 disks, which have not been archived before. All disks work well on my SX-64.

I was able to successfully copy one disk using SCP. I tested it using Vice and it ran well. The other disks were copied into .g64 images but Vice couldn't run them. Vice load the image files and I could "list" the files; when I "run" any program, Vice hangs or the program displays a message saying "bad data or disk alignment error"

I forced my Chinon 5.25" drive into 300 rpm mode and re-imaged the disks, but that didn't help. I'm thinking of buying a 48tpi drive (instead of the Chinin 96tpi), but I'm not sure if this is necessary.

Any help in this regard would be appreciated. Thank you!

[admin]

You are much better off with a 96TPI drive for duplicating ALL disks. What programs are these? If they were commercial disks, you should use INDEX mode with the G64 conversion. Any disk that doesn't convert I can look at the image file and tell you what the issue is.

[Tech]

Great! I sent you two images. Thanks

[admin]

I need these images in .scp format.

[Tech]

I was finally able to copy these disks with great assistance from Jim of CBMStuff.

My disks are original, but they were not created by commercial floppy duplicators. The duplicators utilize the INDEX pulse and start writing tracks on disks at the same position. Commodore disk drives on the other hand have no INDEX pulses and can start writing tracks anywhere. My disks were created by Commodore drives seemingly. When I read them with the SCP card and converted the images to .g64 format, Vice emulator couldn't read them successfully. The emulator expects aligned/indexed tracks in .g64 images.

The solution was to "rotate" each track in the .scp images so that all tracks start at the same line; then to convert the "rotated" .scp into .g64 images. By doing that I was able to load the disk images and successfully run the programs and games in Vice.

Here is how to rotate tracks in .scp images:
1. Launch SCP program, go to Analyze/Editor and load the .scp image (make sure the Disk Types menu is set to C64/128)
2. Find pattern "FF52" that is preceded by tail gaps (lots of A's or 5's). Once one is found, click on the red "52" to make sure it's Sector 0 in the current track.



3. Choose a byte somewhere at the middle of the tail gaps then click on Index Track button.
4. Move to the next track repeat the steps above till the end of image.

Here is an example of a native Commodore 1541 disk image with unsorted tracks:



Here is the disk image after rotating all tracks: