16 Jun
2010
16 Jun
'10
6:40 a.m.
Since I've been failing miserably coming up with a working verilog PLL,
I decided to do something easier tonight.
I captured about 1,000 index pulses from a Sony MPF920-E(if I read date
code right, it's from April 1997) with a 20+ year old floppy disk with a
logic analyzer. I exported the data, and then massaged the data into
some results with Excel.
My average pulse was 200.487ms apart. All pulses were within 55us of
each other, range was 200.464ms -> 200.519.
Standard deviation was 9.46us.
This sounds way way better than the NatSemi AN-505 note of 1-2%.
Is anyone else surprised by this result? I was expecting differences
measured in milliseconds not micros.
Thanks
Keith