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11
770AM -
TOUCH CONTROL /
DESCRIPTION OF LSI
Pin No.
Signal
I/O
Description
20 msec
H : GND
L (-5V)
21
P45
OUT
Back light driving signal.
To change the brightness of the back light (Light emitting diodes LD1 - LD5). The
square waveform voltage is delivered to the back light driving circuit.
To change the brightness of the back light (Light emitting diodes LD1 - LD5). The
square waveform voltage is delivered to the back light driving circuit.
22
P44
IN/OUT
Terminal not used.
23
INT1
IN
Signal coming from encoder.
When the encoder is turned, the contacts of encoder make pluse signals. And
pulse signals are input into INT1.
When the encoder is turned, the contacts of encoder make pluse signals. And
pulse signals are input into INT1.
24
INT0
IN
Signal to synchronized LSI with commercial power source
frequency(50Hz).
frequency(50Hz).
This is basic timing for time processing of LSI.
25
P41
IN
Signal coming from encoder.
Signal similar to INT1. Pulse signals are input into P41.
Signal similar to INT1. Pulse signals are input into P41.
26
P40
IN/OUT
Terminal not used.
27
P77
IN
Signal coming from touch key.
When any one of G11 line keys on key matrix is touched, a corresponding signal
from P23 - P27 will be input into P77. When no key is touched, the signal is held
at "L" level.
When any one of G11 line keys on key matrix is touched, a corresponding signal
from P23 - P27 will be input into P77. When no key is touched, the signal is held
at "L" level.
28
P76
IN
Signal similar to P77.
When any one of G7 line keys on key matrix is touched, a corresponding signal will
be input into P76.
When any one of G7 line keys on key matrix is touched, a corresponding signal will
be input into P76.
29
P75
IN
Signal similar to P77.
When any one of G5 and G9 line keys on key matrix is touched, a corresponding
signal will be input into P75.
When any one of G5 and G9 line keys on key matrix is touched, a corresponding
signal will be input into P75.
30
P74
IN
Signal similar to P77.
When any one of G2 line keys on key matrix is touched, a corresponding signal will
be input into P74.
When any one of G2 line keys on key matrix is touched, a corresponding signal will
be input into P74.
31-33
P73-P71
IN/OUT
Terminal not used.
34
P70
IN
Connected to VC.
35
RESET
IN
Auto clear terminal.
Signal is input to reset the LSI to the initial state when power is applied. Temporarily
set to "L" level the moment power is applied, at this time the LSI is reset. Thereafter
set at "H" level.
Signal is input to reset the LSI to the initial state when power is applied. Temporarily
set to "L" level the moment power is applied, at this time the LSI is reset. Thereafter
set at "H" level.
36
XCIN
IN
Terminal not used.
37
XCOUT
OUT
Terminal not used.
38
XIN
IN
Internal clock oscillation frequency input setting.
The internal clock frequency is set by inserting the ceramic filter oscillation circuit
with respect to XIN terminal.
The internal clock frequency is set by inserting the ceramic filter oscillation circuit
with respect to XIN terminal.
39
XOUT
OUT
Internal clock oscillation frequency control output.
Output to control oscillation input of XOUT.
Output to control oscillation input of XOUT.
40
VSS
IN
Power source voltage: -5V.
VC voltage of power source circuit input.
VC voltage of power source circuit input.
41
P27
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P74 - P77 terminal
while one of G4 and G12 line keys on matrix is touched.
Signal applied to touch-key section. A pulse signal is input to P74 - P77 terminal
while one of G4 and G12 line keys on matrix is touched.
42
P26
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P74 - P77 terminal
while one of G10 line keys on matrix is touched.
Signal applied to touch-key section. A pulse signal is input to P74 - P77 terminal
while one of G10 line keys on matrix is touched.
43
P25
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P74 - P77 terminal
while one of G6 line keys on matrix is touched.
Signal applied to touch-key section. A pulse signal is input to P74 - P77 terminal
while one of G6 line keys on matrix is touched.
44
P24
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P74 - P77
terminal while one of G3 and G8 line keys on matrix is touched.
Signal applied to touch-key section. A pulse signal is input to P74 - P77
terminal while one of G3 and G8 line keys on matrix is touched.
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