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5 - 6
Input port for the PTT switch detection
signal.
Low: While the PTT
switch is
pushed.
Input port for the noise signal from the
FM IF IC (IC9, pin 13).
Outputs serial data to the PLL IC
(IC21, pin 15) and D/A convertor
(IC12, pin 8).
Outputs serial clock signal to the PLL
IC (IC21 pin 14), D/A convertor (IC12,
pin 7), etc.
Input port for the cloning data signal.
Outputs the cloning data signal.
I/O port for data signals from/to the
EEPROM (IC10, pin 5).
Outputs clock signal to the EEPROM
(IC10, pin 6).
Outputs the S5 regulator (Q26–Q28)
control signal.
Low: While the S5 regulator outputs
5 V voltage.
Outputs the T5 regulator (Q24) control
signal.
Low: While transmitting.
Outputs the R5 regulator (Q25) control
signal.
Low: While receiving.
Outputs the transmitting mute switch
control signal to the mute switch
(D29).
High: While muting.
Input port for the PLL unlock signal.
Low: The PLL circuit is unlocked.
PTT
NOIS
SO
SCK
CLI
CLO
ESDA
ESCL
S5C
T5C
R5C
TMUT
ULCK
74
75
76
78
79
80
82
85
86
86
87
88
90
13, 15,
16
29
30
34
35
36
37
38
39
40
41
43
44
45
46
48
49
50
51
69
70
CENC0–
CENC2
REF
PLST
PMFM
MDIO
MSCK
MDIR
MTCK
MTDT
MRDF
DAST
SENC
BEEP
SDEC
CDEC
BATV
LVIN
RSSI
TEMP
CSFT
AF
Output the CTCSS/DTCS signals.
Outputs the reference oscillator cor-
recting voltage. The voltage is applied
to the buffer amplifier (IC24, pin3).
Outputs strobe signals to the PLL IC
(IC21, pin 16).
Outputs the FM/PM modulation
switching signal to the FM/PM switch
(IC13, pin 5).
High: PM is selected.
I/O port for the serial data signals
from/to the base band IC (IC14, pin
11).
Outputs clock signal to the base band
IC (IC14, pin 13).
Outputs serial data control signal to
the base band IC (IC14, pin 14).
Input port for the transmitting MSK
clock signal from the base band IC
(IC14, pin 9).
Outputs MSK data for transmitting to
the base band IC (IC14, pin 10).
Input port for the receiving MSK detec-
tion signal from the base band IC
(IC14, pin 12).
Outputs strobe signals to the D/A con-
vertor (IC12, pin 6).
Output single tone encoder signal.
Outputs beep audio signals.
Input port for single tone decode signal
from the base band IC (IC14, pin 21).
Input port for CTCSS/DTCS signal
from the amplifier (IC19, pin 1).
Input port for the detect signal for con-
necting battery pack’s voltage.
Input port for the PLL lock voltage.
Input port for the S-meter signal from
the FM IF IC (IC9, pin 12).
Input port for the transceiver’s internal
temperature detecting signal.
Outputs shift signal for reference oscil-
lator’s frequency.
Outputs audio control signal.
Low: Outputs audio signals from
speaker.
Pin
Port
Description
number
name
Pin
Port
Description
number
name
5-6-2 CPU (MAIN unit; IC22)