FDC Gap Length? - test-drb@ccmp.vtda.org

17 Jul 2005

Hi Tim,

...
 Part of the calculation is the time it takes the data
separator to re-sync
after each gap.  Now, a "true" 765 doesn't have a data separator so maybe
they leave this out.  It's also true that this number ought to be nearly
constant depending on sector sizes. 
I would assume this is covered by the minimum requirement that Allison was
talking about... Right now I am just trying to find the correct gap sizes
for formatting. Then I will have to worry about the gap size for writing
(which is different, as you obviously don't want to carry through to the
beginning of the next sector).

...
 Do you have the Intel 8272 data sheet?  (This was
Intel's part number
for their 765 clone.  It may not just be a clone but the exact same
mask...).  IIRC there are more details/examples/math in the 8272 data
sheet, including some recommendations for data separators and the good/bad
of different types. 
I do have the Intel data sheet and application notes, however they do not
provide any additional information on selecting the Gap size - just the same
"magic table" that NEC provides.

Regards,
Dave
-- 
dave04a (at)    Dave Dunfield
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