Epson TM-H6000, Service Manual

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Appendix D-62 Product Overview Rev. A
Confidential
Detection Circuits
This printer has detection circuits for paper and various mechanisms. The detection functions
are described in the table below.
TableD-11 Detection circuits
Detector Type
Type of
Sensor
Circuit
TOF Slip detection Transparent
photo Voltage drop of load resistor (R69) is read by AD port of CPU
BOF Slip detection Transparent
photo Voltage drop of load resistor (R68) is read by AD port of CPU
Paper
ejection Slip detection Reflective
photo Voltage drop of load resistor (R66) is read by AD port of CPU
Validation Slip detection Reflective
photo Voltage drop of load resistor (R68) is read by AD port of CPU
Paper
Insertion Paper roll
detection Reflective
photo Logical judgment of voltage drop of load resistor (R147)
Near Paper
End Paper roll
detection Micro switch Logical judgment of switch status by the CPU port.
Voltage Power source
voltage Voltage
potential
divider Potential divider ratio of 24V power source voltage 1/7.2 (R71,
R76) is read by the AD port of the CPU
Impact Head
Temperature Head
temperature Thermistor VCC potential voltage ratio of thermistor resistance value and
R72 is read by the AD port of the CPU
Thermal Head
Temperature Head
temperature Thermistor VCC potential voltage ratio of thermistor resistance value and
R126 is read by the AD port of the CPU
Carriage
Motor
Step-Out Mechanism Transparent
photo Base of Q50 is driven by voltage drop of load resistor (R90);
phase data with no delay is taken out; and logical judgment is
performed by the GA port
Home
Position Mechanism Photo IC Logical judgment of photo IC output is performed by the GA
port.
Lever Timing
Detector Mechanism Photo IC Logical judgment of photo IC output is performed by the GA
port.
Front Cover Case Transparent
photo Logical judgment of load resistor (R88) voltage drop is
performed by GA port.
Rear Cover Case Transparent
photo This signal is used for thermal unit sensor.
Rear Cover
TM-H6000 Case Photo IC Logical judgment of photo IC output is performed by the GA
port.
EP Timing
Pulse EP unit Tacho-gene Waveform shaping (Q19) of sine wave output, and processing
by the CPU interrupt port with hysteresis (U28)
EP Reset EP unit Read switch Logical judgment of the GA port with time constant.
DIPSW DIPSW Pull-up by resistor group (RM1, 2, 3, 4). Reading is performed at
On. Logical judgment is performed by the CPU, GA.