are you sure they're invalid sectors, not there because that's how the format represents copy protected tracks? I think they include multiple copies of weak sectors so that the emulator can read a different copy each time and gets different ones if seeking forward / back the first time (unless i'm thinking of a different format)

I know what was meant to be a simple format was extended to support the most common cpc disk protections at least.

Last edited by Haze; 07/29/17 04:54 PM.