Epson LQ-1170, Руководство по обслуживанию

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REV.-A
Power On
CPU Self Reset
V Line
VCCON
DISC
THLD
RESET
Figure 2-20. /RESET Signal Timing
2.3.3 Sensor Circuits
Figure 2-21 shows the sensor circuits in block diagram form. When the printhead temperature exceeds
the maximum allowed value, the TEMP2 signal and other signals, such as the CRHOME signal, are sent
directly to the CPU. The V line signal passes through the reset circuit before it reaches the CPU.
Terminals to P55 in the CPU are used for the A/D converter. The Vref circuit generates the A/D
converter reference voltage Vref.
C P U
P31
L E V E R 3 1
RESET
NMI P S T 5 2 9 C Line 17
T 2 8
4 . 7 4 1 v
V r e f
V r e f C i r c u i t
Figure 2-21. Sensor Circuit Block Diagram
2 - 1 8