Canon CANOSCAN FB330 series Service Manual page 41

<LED exposure control>
Time required
about 15 seconds
<Peak value detection>
*A
COPYRIGHT © 1999 CANON INC. CANOSCAN FB330/FB630 SERIES REV.0 OCT. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
Standby
LED exposure
control is required?
YES
Detects border between
black and white
Moves scanning unit
forward 2 mm
Sets exposure control mode
R LED ON
Sets LED ON period
Detects peak value
to the CIS
Peak light intensity
to the CIS is higher than
the preset value?
YES
5
Figure 2-8-2
NO
Increases LED ON
NO
LED ON
period is longer than
max. value?
YES
Sets max. LED ON period
CHAPTER 2
period data
NO
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