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Author Topic: MFM decode  (Read 7982 times)

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Offline bloodline

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Re: MFM decode
« on: February 15, 2018, 11:59:23 AM »
Quote from: orange;834196
what does ' length 12656/4' mean in output?
how long is the header, what is its format?
thanks.


edit: is it like this:

OFFSET              Count TYPE   Description
0000h                   8 byte   'UAE-1ADF'
0008h                   4 byte   trackcount
000Ch                   4 byte   0=amigados 1=raw mfm
0010h                   4 byte   tracklength
0014h                   4 byte   tracklength in bits
0018h                   4 byte   0=amigados 1=raw mfm
...





I just cant find '0xAAAA AAAA 4489 4489'   :(

( http://lclevy.free.fr/adflib/adf_info.html#p23 )


I've tried rawread, it doesn't seem to output the MFM data, it just produces and ADF with some extra metadata.

Offline bloodline

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Re: MFM decode
« Reply #1 on: February 15, 2018, 05:37:42 PM »
Quote from: orange;836158
there is an option to force 'raw' mode. if it still doesn't work, you can try with some NDOS diskette.


I'm testing with a normal OFS floppy...

I did use the -r option... but the output is still ordinary bytes not encoded data :(

Offline bloodline

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Re: MFM decode
« Reply #2 on: February 15, 2018, 11:24:55 PM »
Quote from: orange;836167
try -1 and maybe -x

Good call, using -x -1 I definitely get mfm data! But the first sync word is at 370,076 bytes into the file!! that can't be track 0??
« Last Edit: February 15, 2018, 11:34:53 PM by bloodline »