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13
KDC-BT7539U/BT8041U
/BT8141UY/BT838U
Pin No.
Pin Name
I/O
Application
Truth
value table
Processing Operation Description
48
LED CONT TRI I/O Triangle LED luminescence SW
H: LED ON, Hi-Z: LED OFF
49,50
NC
-
Not used
Output L
fi
xed
51
SDA
I/O Data transmission and reception for ROM correction
Output except when data is read
52
SCL
I/O Clock for ROM correction
Output except when clock data is read
53~55
NC
-
Not used
Output L
fi
xed
56
ROTALY2 CW
I
Rotary (Multi key) B input
Pulse width detection
1-pulse/2-click, 15-pulse/360°
57
ROTALY2 CCW
I
Rotary (Multi key) A input
Pulse width detection
1-pulse/2-click, 15-pulse/360°
58
ROTALY1 CW
I
Rotary (VOL) B input
Pulse width detection
1-pulse/2-click, 15-pulse/360°
59
ROTALY1 CCW
I
Rotary (VOL) A input
Pulse width detection
1-pulse/2-click, 15-pulse/360°
60
VCC2
-
Power supply (5V)
Connects PAN5V
61
NC
-
Not used
Output L
fi
xed
62
VSS
-
GND
63~70
NC
-
Not used
Output L
fi
xed
71
SC CON
I
System
μ
-COM communication
Panel operation control
H: Panel operated,
L: Panel operation stopped
72
NC
-
Not used
Output L
fi
xed
73
KR2
I
Key return input
q
74
KR1
I
Key return input
q
75
NC
-
Not used
Output L
fi
xed
76
KS1
I/O Key scan output
q
Switches between output-L and Hi-Z
77
KS2
I/O Key scan output
q
Switches between output-L and Hi-Z
78
KS3
I/O Key scan output
q
Switches between output-L and Hi-Z
79
KS4
I/O Key scan output
q
Switches between output-L and Hi-Z
80
KS5
I/O Key scan output
q
Switches between output-L and Hi-Z
81~90
NC
-
Not used
Output L
fi
xed
91
SA RST
O
Reset output for spectrum analyzer
H: Reset released, L: Reset
92
SA CLK
O
Clock output for spectrum analyzer
93
SA IN
I
Data input for spectrum analyzer
94
AVSS
-
GND
95
NC
-
Not used
Output L
fi
xed
96
VREF
-
A/D analog reference voltage
Connects PAN5V
97
AVCC
-
Power supply (5V)
Connects PAN5V
98~100 NC
-
Not used
Output L
fi
xed
Truth value table
q
KEY MATRIX
KR1 (Pin 74)
KR2 (Pin 73)
KS1 (Pin 76)
TI
AM
KS2 (Pin 77)
MENU
<<
KS3 (Pin 78)
AUDIO
PLAY
KS4 (Pin 79)
ATT
>>
KS5 (Pin 80)
N/A
FM
MICROCOMPUTER’S TERMINAL DESCRIPTION