Canon NP6330 Service Manual page 72

CHAPTER 3 EXPOSURE SYSTEM
a. Turning On and Off the Motor
The motor is turned on and off by the scanning motor drive command (SCMD*).
When the SCMD* command goes '1', the drive pulse command (SCA, SCA*, SCB,
SCB*) goes off so that the motor will not rotate. When the SCMD* command goes '0',
the drive pulse command (SCA, SCA*, SCB, SCB*) goes on to rotate the motor.
b. Controlling the Direction of Rotation of the Motor
The scanning motor rotation command (SCRON) is used to change the order of
output of the drive pulse command (SCA, SCA*, SCB, SCB*).
When the SCRON command is '0', the scanner motor (M2) rotates clockwise,
thereby moving the scanner forward. When the SCRON command goes '1', on the other
hand, the scanner motor (M2) rotates counterclockwise, thereby moving the scanner in
reverse.
c. Controlling the Speed of the Motor
The scanning motor clock pulse command (SCCLK) is used to control the speed of
the motor. The speed of rotation varies when the cycles of the SCCLK command are
varied.
d. Stabilizing the Rotation of the Motor
If variations are noted in the output (amplitude) of the drive pulse signal (SCA, SCA*,
SCB, SCB*), the DC controller PCB accordingly varies the output (analog) of the
reference voltage command (SCVREF) for control so that the amplitude of the pulse
signal remains the same.
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COPYRIGHT © 1997 CANON INC. CANON NP6330 REV.0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)