Canon CANOSCAN FB330 series Service Manual page 36

CHAPTER 2
<Home position detection>
Time required
about 5 to 6 seconds
(Max. 15 sec. returning time
is added depending on the
position of scanning unit)
NOTE: If the peak light intensity
does not reach the black
level even after checking
several lines more, the
home position detection is
in error.
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COPYRIGHT © 1999 CANON INC. CANOSCAN FB330/FB630 SERIES REV.0 OCT. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
Detects black area
Overvoltage was detected?
NO
Sets detection mode for border
between black and white
Sets border detection value
G LED ON
Peak light intensity to CIS
reached black level?
NO
Sets scanning unit return
Returns scanning unit
2
Figure 2-6-3
YES
Sets error flag
Standby
YES
3