Re: need help on adt tansfers-- ADT & AppleWin & sector ordering

[Rubywand <rubywand@swbell.net>]

> "g.ef." writes ...
> 
> Hi everybody.I need some help because i am trying to transfer some files
> that i downloaded from the net .I use ADT with null modem (thanks to apple2
> newsgroups that gave me all the info about them).The null modem is right,the
> programm on both sides seems ok , but when i try to receive a file from my pc to
> the apple i get a <is not a 140k image>  error.Configuration on both systems
> is right(ssc slot,serial port ,speed etc).
 ....


     Did some more experimentation. It turns out that you may be dealing with
perfectly good disk image files which just happen to choke ADT.


     The problem is that users who create disk images using DSK2FILE or ASIMOV
generally use ProDOS sector ordering for making images of 5.25" ProDOS diskettes.
ADT seems to work only with DOS 3.3 ordered disk images. If you transfer a
ProDOS-ordered disk image from PC to your Apple II, it may seem to come in okay;
but, the sectors will be swapped around and the resulting diskette will bomb.


     What's sort of interesting is that AppleWIN does not seem to care about
sector ordering of 5.25" disk images. It will boot a ProDOS disk image created
with DOS 3.3 sector ordering or a DOS 3.3 disk image created with ProDOS ordering
or either kind of image with the 'correct' ordering.

     Meanwhile, a 5.25" ProDOS disk image created using DSK2FILE or ASIMOV with
DOS 3.3 sector ordering, transfers fine from PC-->A2 using ADT and the result is a
good ProDOS diskette.

     And, if the 5.25" DOS-ordered ProDOS disk image file is moved to your Apple
II using ProTERM, Spectrum, etc., you can use DSK2FILE or ASIMOV with DOS 3.3
sector ordering to get a good ProDOS diskette.

     All of which makes one wonder why there is any need to bother with ProDOS
ordering for 5.25" disk images? It looks like all 5.25" disk images should be
created with DOS 3.3 ordering.


     Something else which came from the experiments is that there seems to be no
good reason to bother with ProDOS formatting of target diskettes for 5.25" disk
image--> diskette conversions. It looks like, practically always, the target
diskette should be a plain DOS 3.3 formatted diskette.

     The default volume number for a ProDOS format is 1; but, ProDOS does not care
about volume numbers and DOS 3.3 stuff usually works best with the default (254)
you get with a simple INIT HELLO.




Rubywand