TSC TDP 248M, Service Manual

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31
TTP-248M/2410M Bar Code Printer
Service Manua
l
2. Selecting AUTO GAP to detect label will get a value of tension, and then
selecting the MANUAL GAP.
When sensor detects white paper:
LCD displays Reflect the voltage of receiver (PIN 3)
≦
2.10V
When sensor detects the Black mark or does not detect paper:
LCD displays Not Reflected the voltage of receiver (PIN 3)
≧
1.26V
U1/12
U1/10
GND
VCC
3
2
1
4
11
U5A
LM324
R63
100
GND
VDD
GND 8 9
U3D
74HC14
10 11
U3E
74HC14
5
6
7
U5B
LM324
R65
100
GAP_E
BM_E
R26
10K
R27
4.7K
R66
100
10
9
8
U5C
LM324
R126
100
MOTER_C
VDD
GND
GND
Q14
HSC945
Q15
HSC945
1
2
3
4
5
6
7
JP12
GAP_
U1/207
U1/206
GAP_SENSER
EM SEN
DA0/AN7/PTL7
MOTER E
Fig. 3.10 Black mark/ Gap Sensor Circuit
Peel-off Sensor
The voltage of the sender is about 1.18V (1.17V~1.19V)
When sensor does not detect paper, the voltage of receiver (PIN 2) is
≧
2.10V
When sensor detects the paper, the voltage of receiver (PIN 2) is
≦
1.26V
CASE_OPEN
GND
VCC
R72
100 R43
10K
1 2
U4A
74HC14
PEEL_SENS
1
2
3
4
5
JP32
5PIN
Fig. 3.11 Peel-off Sensor Circuit