Re: .DSK Image does not work on real machine, but, works fine in an Emulator

[pausch@saaf.se (Paul Schlyter)]

In article <3A782D5F.7D9F875F@topmail.de>,
Patrick Schaefer  <patrick.schaefer@topmail.de> wrote:
 
> olcott schrieb:
> 
>> The problem is this file will not run on a real Apple IIe,
>> but, does
>> run on an Apple IIe emulator. How could a DSK work on
>> an emulator, but, NOT, work on a real machine?
> 
> The logical sector numbers do not follow the physical ones, there ist an
> interleave. DOS sector 1 is on physical sector 1, DOS 2 on phys. 7 and
> so on. This gives the computer some time to process the data before the
> next sector has moved towards the RW head.
> 
> DOS 3.3 and ProDOS use different interleaving schemes. 
> 
> ADT expects the disk images to be in DOS order, that means using the DOS
> 3.3 interleave. That means block 1 is written on physical sector 1, bloc
> 2 on 7 and so on. 
> 
> NuLib creates image files in ProDOS order. If you download a *.SDK image
> and extract the *.dsk file, it won't work with ADT because the sectors
> are scrambled. However, the emulator programs can recognize the image
> format and therefore run both types. (They look at the catalog track)
 
WHICH catalog track?  The DOS or the ProDOS catalog track?
 
And what about dual-OS disks, where the outer half is a ProDOS disk
while the inner half is a DOS 3.3 disk?
 
Too bad ADT just don't use physical sector order, because if it did,
this would not have been an issue.
 
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