Re: Disk II Phase Question

["Bryan Parkoff" <nospam@nospam.com>]

Hello,

    I have collected enough information what I needed to know.  I have seen 
that there are some images with extension .NIB.  I suspect that Apple II 
Emulators can run *.nib using copy protected software, but someone claim to 
turn off copy protected.  I wonder why.
    We should be able to copy "bit by bit" from copy protected diskette such 
as spiral into *.nib.  It is like "Where in the World is Carmen Sandiego?" 
for Apple II.  Do you think that Apple II Emulator will be able to run copy 
protected software *.nib that it contains "Where in the World is Carmen 
Sandiego?" rather than *.dsk (turned off copy protected).
    If it is very possible, I should be able to write IWM routine that it 
does include logic sequencer and MPU 6502 cycle by cycle.  (I have already 
written MPU 6502 cycle by cycle, but I would try to simulate IWM logic 
sequencer for curious.  No time waste...)
    I don't like *.nib that it has 232,960 bytes.  It should be more than 
232,960 bytes because it has a flexibility to write 18 sectors insead of 16 
sectors per track up to 40 tracks.  Eighteen sectors should be enough for 
real Apple II diskette that I did myself.  Expect to reach 180K instead of 
140K.  If stick to 16 sectors, it would reach 160K.
    Maybe, I should name extension *.A2D.  "*.A2D" stands for Apple II 
Diskette.  What do you think?

Bryan Parkoff

"Jplcsch" <jplcsch@wanadoo.fr> wrote in message 
news:41ea3b10$0$19418$8fcfb975@news.wanadoo.fr...
> Look the routine of  flight simulator II, it's really the maximum you can
> put on a track (18 pages with a small amount for the translation table!)
> on look the track with CIA or any other utility
> to help you:
> Syncro are $FE
> start of track $D5 $AA $D5
> after you found a transalation table
> a close byte $94
> the marker of every sector (just one) $D5
> 18 pages  (if you unassemble the read routine you'll found a loop with $12
> to test the nb of sectors read on the track)
> checksum
> close markers for the track $DE $AA
> good luck
>
>
>
> "Eric Smith" <eric-no-spam-for-me@brouhaha.com> wrote in message
> qhmzv9n2zb.fsf@ruckus.brouhaha.com">news:qhmzv9n2zb.fsf@ruckus.brouhaha.com...
>> "Bryan Parkoff" <nospam@nospam.com> writes:
>> >     I understand now.  The reason is that I say ($5F00) 24,320 bytes or
>> > 194,560 bits per track.
>>
>> The number of nybbles per track varies because normal nybbles are
>> 8 bits each, while self-sync nybbles are either 9 or 10 bits (determined
>> by whether the FF pattern is written to the shift register every 36 or 40
>> microseconds, instead of 32 microseconds for a normal nybble).
>>
>> There are nominally 50,000 bit positions on a track, which means that
>> normally there would never be more than 6250 nybbles per track.  Given
>> the variation in drive speeds, you might see up to 5% higher in practice.
>
>