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4 - 4
4-5 PORT ALLOCATIONS
• CPU (IC51)
• D/A CONVERTER (IC57)
PIN
NO.
LINE
NAME
DESCRIPTION
I/O
1
CDEC
Tone signal (CTCSS/DTCS)
decoding input.
I
2
STONE
Tone signal (5/2 TONE, DTMF,
BIIS) decoding/encoding .
I/O
13
CSFT
Clock frequency shift.
H=Clock frequency is shifted.
O
14
NWC
R X m o d e ( n a r r o w / w i d e )
switching.
L= While receiving in the narrow
mode
O
15
EPTT
External PTT input.
H=An external PTT is pushed.
I
16
ATX
Automatic TX control for VOX
mode.
H=Microphone input is detected.
O
17
BEEP
Beep sounds. (Square waves)
O
18
AFON
AF power AMP control.
H= A F p ow e r A M P ( I C 5 5 ) i s
activated.
O
19
SCK
Common clock.
O
20
SO
Common serial data.
O
22
KEY2
[UPPER]
key input.
L=Pushed
I
23
KEY1
[LOWER]
key input.
L=Pushed
I
24
PLST
PLL strobe.
H=Load enable.
I/O
25
DAST
D/A converter strobe.
H=Load enable.
I/O
26
ESDA
EEPROM data.
I/O
27
ESCL
EEPROM clock.
I/O
28
R5C
Power supply switching control.
H= S u p p l y i n g c u r r e n t t o t h e
receiver circuits ("R5"line).
O
29
T5C
Power supply switching control.
H= S u p p l y i n g c u r r e n t t o t h e
transmitter circuits ("T5"line).
O
30
S5C
Power supply switching control.
H= Supplying current to the RX/
TX common circuits ("S5"line).
O
31
PWON
Power supply switching control.
H= The transceiver's power is
ON.
O
32
IPTT
Internal PTT input.
L=PTT pushed.
I
33,
34,
36
CENC2,
CENC1,
CENC0
CTCSS/DTCS signal.
O
37–
40
CBI0–
CBI3
[ROTARY SELECTOR]
input.
I
41
DUSE
Frequency response switching.
H=DTCS encoding
O
42
RLED
Busy LED (Green) control.
L=LED lights. (Squelch open)
O
43
TLED
Busy LED (Red) control.
L=LED lights. (Transmit)
O
47
MGC0
MIC gain control.
O
48
MGC1
MIC gain control.
O
49
CLI
Cloning data.
I
50
CLO
O
PIN
NO.
LINE
NAME
DESCRIPTION
I/O
51
ADSW
A/D conversion select.
H=RSSI input, L=BATV input
O
53
NOIS
Noise level detect.
H=Squelch close
I
54
UNLK
PLL unlock detect.
I
55
RMUT2
RX AF mute switch control.
L=AF mute.
O
56
RMUT1
RX AF mute switch control.
L=AF mute.
O
57
MMUT
MIC mute switch control.
L=MIC mute.
O
58
TMUT
Transmission mute.
L=TX inhibit.
O
59
MDET
External microphone connection
detect.
I
60
LVIN
Lock voltage input.
I
61
TEMP
Temperature sensing voltage.
I
62
AFVI
[VOLUME CONTROL]
input.
I
63
VOXV
Microphone input sensing voltage.
I
64
AD5
Remaining battery voltage.
(or)
RSSI voltage.
( The input signal depends on the
status of pin 51.)
I
PIN
No.
LINE
NAME
DESCRIPTION
23
T1
(TXPO)
BPF tuning voltage
TX power control
24
T2
BPF tuning voltage
7
REF
Reference frequency adjust voltage.
8
LVA
Additional lock voltage adjustment.
11
SQLC
Squelch threshold setting.
12
TENC
CTCSS deviation adjustment.
19
BAL
DTCS balance.
20
VRAF
Max. deviation/AF volume adjustment.