Document Scanning Sequence - Canon CanoScan 9900F Service Manual

D. Document Scanning Sequence

1. Document Scanning Sequence

Sequence
Home Position
Sensor
Scanning Lamp
ON Signal
Drive Motor
Interface Signal
Seqence
After the scanner self test is
completed until the scanner
Standby
receives a scan command from
the host computer
From the scanner receives a
Setup
scan command until it starts
scanning
After the scanner starts scanning
until whole scan area specified
Scanning Unit
by the host computer is scanned
Forward
After the scanning unit starts
Scanning Unit
moving backward until it returns
backward
to the home position
COPYRIGHT 2003 CANON INC. CANOSCAN 9900F REV.0 FEB. 2003 PRINTED IN JAPAN (IMPRIME AU JAPON)
Scan Command
Setup
Standby
(Scans 9 lines for
RGB each)
Figure 2-4
Operation
To maintain the scanner ready
for scan
To execute calibration for setting
light exposure time, gain data and
shading data
To execute image processing
according to the command from
the host computer while scanning
and send imada data to the
host computer
To return the scanning unit to the
home position to ready for the
next scan
Table 2-1
Scanning Unit
Scanning Unit forward
backward
Purpose
CHAPTER 2
Standby
Remarks
The data is stored in DRAM
Home position is detected
by the home position sensor
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