29 Jun
2010
29 Jun
'10
11:23 p.m.
On 28/06/2010 22:15, Philip Pemberton wrote:
On 28/06/10 20:31, Tony Duell wrote:
Am I missing something, or is that too low by a factor of about 8 or 9
(the number of inches along a line)? It's somewhere in the region of
24MHz, surely.
--
Pete Peter Turnbull
Network Manager
University of York
I don't know off the top of my head, but it
should be farily easy to
measure the speed of rotation of the motor. Each revolution would
generate<n> beam detect pulses (the output of the photosensor) where<n>
is the number of sides of the polygonal mirror.
Well, working backwards from DPI and print speed gives about 3MHz dot
clock:
300DPI * 11 inches (paper height) * 3ppm = 9900 lines per minute
(thus, the line rate is 9900Hz, or 9.9kHz)
9900lpm * 300 dots per line = 2.97e6
(thus, the pixel rate is 2.97MHz)