| Author: | Pete Rittwage (registered user: 558 posts ) |
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| Date: | Thu, Jul 08th, 2010 @ 09:30 ( . ) |
I believe it's counting/measuring the sync length on track 19 and then checking for the GCR pattern after- it's been years since I looked at it. I could also be checking the exact length of the track using timers. Writing it back was hit and miss. I think I tried a few times and eventually it was close enough to work, but it is just finicky. Disassemble it to find out if you're curious what it's looking for- you can use the VICE monitor and look at the code it's running from drive RAM between 0300-07ff on dev 8: The address it shows when you go to dev 8: will give you a clue to the area of the code to look for. If you don't know 6502 or how the drive works, you are flying blind. |
7/08/2010 @ 20:37----hyper active 7/08/2010 @ 20:49--------Pete Rittwage --- 0 Users Online --- 0 Recent Unique Posters |