Canon WS8400 Service Manual page 74

Chapter 2
1.Cut media feeding starts
2.Media trailing edge detection
1) Feed the media forward and tentatively detect the media trailing edge with the media sensor (temporarily stop feeding when detected).
2) Feed the media backward and detect the media trailing edge with the media sensor (stop feeding when detected).
3.Registration sensor calibration
1) Move the registration sensor over the media.
2) Determine sensor output and check the registration sensor input value over the media.
3) Drive the carriage and move the registration sensor over the media.
4) Check the sensor input value over the platen.
5) Determine the sheet edge threshold.This is performed each time the media is loaded since the sensor input value varies depending
on the media type.
4.Media width detection
1) Drive the carriage and move the registration sensor over the media to detect the media left edge.
2) Drive the carriage and detect the media left edge (momentarily stop carriage return movement when detected).
3) Drive the carriage and move the registration sensor over the media.
4) Detect tentatively the media right edge (temporarily stop return movement of the carriage when
detected).
5) Drive the carriage and move the registration sensor to media right edge detection start position (30mm inside the media right edge tentative detection
position: on media).
6) Drive the carriage and detect the media right edge (momentarily stop carriage forward movement when detected).
5.Media leading edge detection (start)
1) Drive the carriage and move the registration sensor 30mm in the forward direction from the media right edge.
2) Feed 300mm forward from the media set position.
6.Media leading edge detection
1) Drive the carriage and move the registration sensor 30mm in the forward direction from the media left edge.
2) Feed 50mm forward from the media set position.
3) Feed the media backward and detect the leading edge of the media (stop feeding when detected).
7.Media leading edge detection (continue)
1) Drive the carriage and move the registration sensor 30mm in the forward direction from the media left edge.
2) Feed 50mm forward from the media set position.
3) Feed the media backward and detect the leading edge of the media (stop feeding when detected).
8.Media leading edge detection(shut down)
9.Media skewing detection
1) Drive the carriage and detect the media right edge (stop carriage forward movement when detected).
2) Compare with media right edge determined during media width detection, and determine the skew amount (skew amount depends on the detection
precision).
10.Media leading edge detection (recovery)
1) Move the media sensor to the leading edge detection interrupt position.
2) Feed the media backward and tentatively detect the media leading edge (stop feeding when detected).
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1.Cut media feeding starts
2.Media trailing edge
detection
3.Registration sensor
calibration
4.Media width detection
5.Media leading edge
detection (start)
6.Media leading edge
detection
Detected
7.Media leading edge
detection (continue)
11.Media skewing detection
12.Cut media feeding ends
13.Print
Unable to detect
8.Media leading edge
detection (shut down)
9.Media skewing detection
10.Media leading edge
detection (recovery)
F-2-25