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Pin
Port
Description
number
name
Pin
Port
Description
number
name
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
VIN
REMOTE
SD
CTCIN
LOCKV
THERMC
SBATT
CONT
CTCOUT
BEEP
BPCPI
NOISE
PDA2/UL
PDA1/UL
DAST
IOST
PLST2
PLST1
CLONEOUT
Input port for the over-voltage detec-
tion from connected battery pack or
external power supply.
Input port for remote control signals
from an optional HM-75A microphone
via the [MIC] jack.
Input port for the S-meter voltage.
Input port for CTCSS decoded sig-
nals.
Input port for the PLL lock voltage.
Input port for the tranceiver’s internal
temparature.
Input port for the VCC voltage (con-
nected battery voltage).
Outputs control signal for the LCD
contrast.
High : The LCD contrast is deep.
Outputs CTCSS signals while trans-
mitting.
Output port for:
• Beep audio signals while receiving.
• DTMF signals or 1750 Hz Europe
tone signal while transmitting.
[EUR], [ITA], [UK]
Input port for the bias control voltage
to judge kinds of battery types.
High : Supply the bias control volt-
age.
Input port for the noise signal (pulse-
type) from the IF IC (RF unit; IC 701,
pin 13).
Outputs data signals to the PLL IC2
(RF unit; IC802, pin 4).
Input port for the PLL unlock signal
from the PLL IC2 (RF unit; IC802, pin
4).
Outputs data signals to the PLL IC1
(RF unit; IC801, pin 5).
Input port for the PLL unlock signal
from the PLL IC1 (RF unit; IC801, pin
5).
Outputs strobe signals to the D/A IC
(LOGIC unit; IC5, pin2).
Outputs strobe signals to the I/O IC
(RF unit; IC2, pin 1 and IC3, pin 1).
Outputs strobe signals to the PLL IC2
(RF unit, IC802, pin5).
Outputs strobe signals to the PLL IC1
(RF unit, IC801, pin 3).
Output port for the cloning signal.
20
21
22
23
24
25
26
27
28
29
30
31
32
33
39
41
42
43–46
47, 48
49–54
55, 56
Input port for the cloning signal.
Outputs T4 regulator control signal.
High : While transmitting.
Outputs R3 regulator control signal.
High : While receiving.
Input port for the reset signal from
Q151 (LOGIC unit).
Outputs control signal for charger cir-
cuit (RF unit; Q5).
High : While battery is charging.
Outputs control signal for the AF
amplifier requlator circuit.
High : Activates the AF amplifier cir-
cuit.
O3C regulator control signal
(LOGIC unit; Q142 and Q145).
Outputs control signal for the Europe
tone and DTMF.
Low : Activates the Europe tone.
High : Activates DTMF.
Outputs BUSY LED control singal.
Low : The BUSY LED is ON.
Outputs LCD backlight control signal.
High : Lights ON.
Outputs control signal for the regulator
secton of MIC amplifier (LOGIC unit;
IC301).
Low : Activates the MIC amplifier
circuit.
Outputs AF mute and MIC mute con-
trol signals.
High : Mute is ON.
Input port for the [POWER] switch.
Input port for the RESET signal from
IC142, pin 1 (LOGIC unit).
Input port for the [PTT] switch.
Outputs clock signal to the PLL IC1
(IC801), PLL IC2 (IC802), D/A IC (IC5)
, I/O IC (IC2, IC3) on the RF unit and
EEPROM IC (LOGIC unit; IC2).
Data bus line for the EEPROM
(LOGIC unit; IC2).
Input ports for key matrix.
Input ports for Initial matrix.
Outputs port for key matrix.
Input port for the up/down signal from
the main dial (LOGIC unit; S1).
CLONEIN
TXC
R3C
CPUHV
CHGC
AFON
PCON
TCON
BLED
LIGHT
MICC
RM/MM
POWER
RESET
PTT
CK
ESIO
KR3–KR0
I1, I2
KS5–KS0
DICK,
DIUK
4 - 7
4-5-3 CPU (LOGIC UNIT; IC1)