Service manual

CHAPTER 2
2 - 5 COPYRIGHT  2002 CANON INC. CANOSCAN 8000F REV.0 OCT. 2002 PRINTED IN JAPAN (IMPRIME AU JAPON)
D. Document Scanning Sequence
Figure 2-4
Table 2-1
Standby
Setup
Scanning Unit
Forward
Scanning Unit
backward
Seqence
After the scanner self test is
completed until the scanner
receives a scan command from
the host computer
From the scanner receives a
scan command until it starts
scanning
After the scanner starts scanning
until whole scan area specified
by the host computer is scanned
After the scanning unit starts
moving backward until it returns
to the home position
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
Remarks
Operation
The data is stored in DRAM
Purpose
To return the scanning unit to the
home position to ready for the
next scan
Home position is detected
by the home position sensor
Standby
Scanning Unit forward
Drive Motor
Sequence
Home Position
Sensor
Scanning Lamp
ON Signal
Interface Signal
Scan Command
Setup
Standby
Scanning Unit
backward
(Scans 9 lines for
RGB each)