Imagedisk 1.17

[Chuck Guzis]

On 2 Aug 2007 at 1:09, Jim Leonard wrote:

> Chuck Guzis wrote:
> > When I do my delay, I wait for the bit to flip once, then again, then 
> > again.  Simple--even my old NT and 98 diskette device drivers worked 
> > with it.
> 
> What about interrupt jitter?  Or did you lock out certain interrupts 
> while you were measuring?

With the 765, jitter and intervening interrupts is immaterial.  You 
need the delay when issuing commands and reading status to ensure 
that a *minimum" time has passed.  If an interrupt intervenes, it's 
immaterial, as you've satisfied the minimum delay criterion.

If you needed absolute precision, I suppose you could mask or disable 
interrupts, but in the case of disk commands, it's not necessary.

Cheers,
Chuck