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4 - 4
4-5 PORT ALLOCATIONS
• CPU (LOGIC UNIT: IC1)
• D/A CONVERTER (MAIN: IC5)
• SHIF REGISTER (MAIN: IC2)
Pin
No.
Line
Name
Description
I/O
1
MICSEL Microphone connection detect.
I
3
TONE
DTMF/BEEP/1750Hz tone signal.
O
4
CTCOUT
Tone signal (CTCSS/DTCS) encoding
output.
O
10
RESET
CPU (LOGIC UNIT: IC1) reset signal.
H=The CPU is reset.
I
15
EXTSTB
Shift register (MAIN UNIT: IC2) serial
strobe.
O
16
DASTB
D/A converter (MAIN UNIT: IC5)
strobe.
O
17
DATA
Shift register (MAIN UNIT: IC2) serial
data.
O
18
EXTCK
Shift register (MAIN UNIT: IC2) serial
clock.
O
19
NOIS
Noise level detect.
I
20
CLIN
Cloning data.
I
21
CLOUT
Cloning data.
O
22
PWRSW
[ ]
input.
L= Pushed.
I
23
OE
Shift register (MAIN UNIT: IC2) chip
enable.
O
24
PCON
Main power supply line control.
H=During the transceiver is ON.
O
25
UNLK
PLL unlock detect.
L=Unlocked.
I
26
PLLCK
PLL IC (MAIN UNIT: IC1) serial clock.
O
27
PLLDATA PLL IC (MAIN UNIT: IC1) serial data.
O
28
PLLSTB PLL IC (MAIN UNIT: IC1) strobe.
O
29
VOL-
DATA
Electronic volume (LOGIC UNIT: IC25)
serial data.
O
30
VOLCK
Electronic volume (LOGIC UNIT: IC25)
serial clock.
O
71,
72
KS1,
KS0
Key input ports.
I
76–
79
KR3–
KR0
I
80
LVIN
Lock voltage input.
I
81
HVIN
Power source voltage.
I
82
WX
Weather alert signal.
I
83
CTCIN
Tone signal (CTCSS/DTCS) decoding
input.
I
84
SQLV
[SQL]
input.
I
85
VOLV
[VOL]
input.
I
86
MICUD
Up/down key on the microphone.
I
87
SD
RSSI voltage from the IF IC (MAIN
UNIT: IC3).
I
88
TEMP
Temperature sensing voltage.
I
89
IDET
TX power AMP current fl ow sensing
voltage.
I
94
ESCK
EEPROM (LOGIC UNIT: IC5) serial
clock.
O
95
ESDA
EEPROM (LOGIC UNIT: IC5) serial
data.
I/O
97
DICK
Rotary encoder (LOGIC UNIT: S9)
pulse. (Phase A)
I
98
DIUD
Rotary encoder (LOGIC UNIT: S9)
pulse. (Phase B)
I
Pin
No.
Line
Name
Description
6, 7
SQLIN
Noise squelch level adjustment.
8
T3
Tuned BPF tracking voltage adjust-
ment.
11
T2_APC
RX: Tuned BPF tracking voltage ad-
justment.
TX: Transmit output power adjustment.
12
T1
Tuned BPF tracking voltage adjust-
ment.
19
FC
Reference frequency adjustment.
20
REFMOD
Reference oscillator deviation adjust-
ment.
22, 23
MOD
VCO deviation adjustment.
24
SQLATT
Squelch attenuator level adjustment.
Pin
No.
Line
Name
Description
5
PLLSW
PLL lockup time control.
H=Fast lockup mode.
6
TXMUTE
TX mute control.
L=Mute.
7
NWC
Narrow/Wide mode switching control.
H=Wide mode.
11
SHIFT
VCO switching control.
H= While receiving. (The RX VCO
(Q14, D10–D11, L6) is activated)
L= While transmitting. (The TX VCO
(Q13, D7–D9, L5) is activated)
12
T8C
Power supply line “T8C” control.
H=While transmitting.
13
RXC
Power supply line “R5V” control.
H=While receiving.
14
SPMUTE
Speaker mute control.
H=Mute.
Pin
No.
Line
Name
Description
I/O
99
PTT
[PTT]
input.
H= Pushed.
I
100
REMO
Microphone connection detect.
H=Connected.
I