4 - 4
Input port for CTCSS signal for decod-
ing.
Input port for the reset signal.
Output reference oscillator for the
CPU control signal.
Output clock signal to the PLL (IC1)
and EEPROM (IC7) ICs, etc.
Input port for the data signals from
EEPROM (IC7), etc.
Output data signal to the PLL (IC1)
and EEPROM (IC7) ICs, etc.
Input port for PLL unlock signal from
the PLL IC (IC1).
High: During unlock
Input port for the cloning signal.
Output port for the cloning signal.
Outputs strobe signals to the PLL IC
(IC1).
Input port for noise signals (pulse
type) from the FM IF IC (IC2, pin 13).
Outputs LCD contrast control signal.
High: When normal level is selected.
Output ports for key matrix.
Outputs the analog switch (IC4) con-
trol signal.
Low : While DTMF or ANI signals
are output.
Outputs the analog switch (IC4) con-
trol signal.
Low : While muted.
Input ports for key matrix.
Outputs R5 regulator control signal.
Low : While receiving
Output S5 regulator control signal.
Low : While power is ON.
Outputs transmit output power select
(HIGH or LOW) signal.
Low : HIGH power is selected.
Input ports for the [PTT] switch.
High: While [PTT] is pushed
Outputs LCD backlight control signal.
High: When backlighting is ON
Outputs the regulator circuit control
signal for the AF amplifier.
High: While AF amplifier is activat-
ed.
Pin
Port
Description
number
name
4-5 PORT ALLOCATIONS
CPU (IC8)
1
9
11
12
13
14
15
16
17
18
19
26
36–41
42
43
44–47
48
49
50
51
52
53
CIN
RESET
CSIFT
SCK
SI
SO
UNLK
CLIN
CLOUT
PLST
NOIS
CONT
KS0–KS5
MMUT
RMUT
KR0–KR5
R5C
S5C
TXC
T5C
LIGHT
AFON
Output ports for:
• tunable bandpass filter control
signal while receiving.
• reference signal for the APC circuit
while transmitting.
Outputs beep audio signals.
Outputs DTMF signals while pushing
the keypad during transmit.
Input port for the [PTT] switch.
Input port for internal temperature
detection.
Input port for the S-meter signal from
the FM IF IC (IC2, pin 12).
Input port for overvoltage detection
from the connected power supply or
battery pack.
Pin
Port
Description
number
name
54–60
90
91
94
96
98
100
T4/PWR
BEEP
DTMF
PTT
TEMP
SD
VIN
