Re: Weak Bits

From: Pete Rittwage (
Date: 2007-12-04 22:53:52

> Hi !
> I would like to know more about weak bits. What are weak bits ? How can
> they
> be stored in the
> GCR file format ? what would be necessary to support weak bits if you want
> to emulate the r/w
> head for drive emulation ?

As for how they are represented in the G64 format, it is a raw GCR stream,
so it will have the bytes that the drive hardware saw at the time of
imaging.  In N2G (and now NIBTOOLS) I detect these areas and zero the
bytes out.  The emulator authors know what to do with these zeroed bytes
(CCS, Hoxs) and return random (sort of) data to the emulated 15x1. 
WinVICE has support for it as a patch from me (and improved by Womo) but
it is commented out in the source- you have to uncomment and recompile the
updated rotation.c

Pete Rittwage
C64 Preservation Project

       Message was sent through the cbm-hackers mailing list

Archive generated by hypermail pre-2.1.8.