CHAPTER 2
2 - 27
COPYRIGHT © 1999 CANON INC. CANOSCAN FB330/FB630 SERIES REV.0 OCT. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
B. CanoScan FB330P/FB630P Document Scanning Sequence
Figure 2-14
Table 2-1
HPDET
STUP
SCFW
SCAN
SCRTN
STBY
STBY
5 - 6
G LED only
Sequence
Time required (s)
Scanning unit drive motor (M1)
LED ON signal
Interface signal
(Data 1-8)
Home position
Scan command is received
A4, 300 dpi, 100%, 24 bit color
:Reverse
Scanning unit position
Document
scan area
After a power on sequence is
completed until the scanner
receives a scan command
from the host computer.
To maintain the scanner ready
for scan.
After the scanner received a
scan command until the home
position is detected.
To detect the border between
black and white to define the
home position.
If the detection of the border
between black and white is failed,
the scanning unit stops there and
proceeds to the next step.
After the home position is
detected until document scan
starts.
To make a gate array setting,
buffer RAM initialization, etc. as
a preparation for scan.
After the scanning unit starts
moving forward until it
reaches the starting position
of the scan area specified by
the host computer.
To move the scanning unit with
a uniform speed to the vertical
scanning position specified by
the host computer.
After the scanning unit starts
scanning until all area
specified by the host
computer are scanned.
To perform various image
processing according to the
command from the host
computer and transmit the
image data during scan.
After the scanning unit starts
moving backward until it
returns to the home position.
To return the scanning unit to
the home position to ready for
the next scan.
The distance to the home position
is calculated by the distance from
the detected home position to the
position the scan is completed.
Sequence
STBY
(Standby)
HPDET
(Home position
detection)
STUP
(Setup)
SCFW
(Scanning unit
forward)
SCAN
(Document scan)
SCRTN
(Scanning unit
return)
Purpose
Remarks
