TCP/IP for RT-11 - test-drb@ccmp.vtda.org

23 Aug 1998

...
 Other than the media will not store the same amount
without resorting 
to RX33 (or similar) formatting. The RX02 is 512kb on 77 tracks and 26 
sectors of 256 bytes.  That really doesn't work on 5.25 floppies.  So 
likely the format is a bit more munged.  Anyhow calling something that's 
media incompatable a "RX02" sorta makes for great confusion.  Hell I 
have a solidstate serial disk that emulates a TU58 that uses ram for 
storage, it's a TU58 to the software (DD driver) and it's 256k per tape 
but it's hardly media compatable.  So if someone says RX02 it means 8" 
SSDD floppy using DEC M^2FM encoding of the data fields and is able to 
read and write RX01 media.  Even a DSD880/120 obeyed that! 
Thanks, Allison... exactly my point...

And in fact, early versions of DSDs didn't look exactly like RL01s,
they were larger... requiring changes to the driver so that they
would work.  But these changes were NOT made to the distributed
sources... the owner's manual for the DSDs described the changes
to make.

					Megan Gentry
					Former RT-11 Developer

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