Epson SQ-B50/2550 Technical Manual page 108

REV.-A
2.4.1.9
Control Circuit for the Paper Change Mechanism
Figure 2-43 is a block diagram of the control circuit for the paper change mechanism. (Refer also to
Location 2-H of the Seima Board Circuit Diagram in the APPENDIX).
The release solenoid is driven in accordance with the RSEN signal sent from the general-purpose port
P10 of the PIF gate array (12C).
When RSEN is HIGH,
+
24VDC is applied to the release solenoid; the release sensor signal is also input
to PIF port P11. An RSEN signal LOW is used to indicate that tractor feed has been selected.
Figure 2-44 shows the operating waveforms for the release solenoid drive.
+24
PlO
PII
PIF1I2CJ
EOSA24GA
......-
+
-
RS+
-
Release
-
Solenoid
RSEN
-
Driver
-
RS-
Circuit
-
+
GH
RU1rocfor) ease
sor
Rei
Sen
Release
Solenoid
Figure 2-43 Block Diagram of Paper Change Mechanism Control Circuit
~
,
....
......
I . ....
eo~
BY
0
181
o
III
Upper: RSEN signal
Lower: Collector for transistor Q20
Figure
2-44.
Waveforms for Release Solenoid Drive Operation
2-40