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4 - 5
Pin
Port
Description
number
name
Pin
Port
Description
number
name
1
2
3
5
6
7
8
16
17
18
20
21
22
23
27
28
29
31
83
84
85
89
90
91
92
CONT1
CONT2
BEEPM
CH16
CH
H/L
HANG
PCK
PSTB
PDATA
ICFC
BPLVL
ECK
EDA
HI/LO
RRXD
RTXD
BPFV
TMUT
NMEAI
NMEAO
SQLV
SQL
LBAT
TXDET
Outputs control signal for the LCD
contrast.
Outputs beep audio signal.
Input port for the CH16 switch.
Low: While CH16 switch is pushed.
Input port for the CH switch.
Low: While CH switch is pushed.
Input port for the H/L switch.
Low: While H/L switch is pushed.
Input port for the MIC hanging signal.
Low: While MIC is pull-up.
Outputs clock signal to the PLL IC
(MAIN unit; IC2, pin 4).
Outputs strobe signals to the PLL IC
(MAIN unit; IC2, pin 3).
Outputs data signals to the PLL IC
(MAIN unit; IC2, pin 5).
Outputs control signal to swtich NMEA
or ICF3.
Outputs beep volume control signal.
Low: Beep audio is maximum.
Outputs clock signal for the EEPROM
(IC2, pin 6).
I/O port for the EEPROM data signals.
Output port for RF output power (High
or Low) select signal.
Input port for the cloning data.
Output port for cloning data.
Outputs bandpass filter select signals.
Low: Receiving more than 160 MHz.
High: Receiving less than 160 MHz.
Outputs transmit mute signal.
High: While transmitting.
Input port for DS-100 data.
Outputs cloning data signal.
Input port for the squelch volume
level.
Input port from the FM IF IC (MAIN
unit; IC1) for the squelch operation.
Input port for the connected power
supply voltage detection (low battery
indicator).
Input port for TX LED control signal.
93
94
95
96
97
98
99
Input port for the HM-132 functions.
2.02 V: [UP] is pushed.
3.00 V: [DN]] is pushed.
3.84 V: [16/C] is pushed.
Input port for the PTT switch from HM-
132.
Low: While PTT is pushed.
Input port for the TAG switch.
Low: While TAG switch is pushed.
Input port for the SCN switch.
Low: While SCN switch is pushed.
Input port for the UP switch.
Low: While UP switch is pushed.
Input port for the DOWN switch.
Low: While DOWN switch is pushed.
Input port for the PLL unlock signal.
Low: While PLL is locked.
KEYM
PTT
TAG
SCN
UP
DN
UNLK
4-7 PORT ALLOCATIONS
4-7-1 CPU (LOGIC BOARD; IC1)
CONT1
0
1
CONT2
0
1
CONTRAST
LIGHT
DEEP
Pin
Port
Description
number
name
4
6
13
14
RMUTM
PTTM
SEND
RCV
Outputs the AF mute swtich (MAIN
unit; IC5) control signal for main body.
Low: While squelched
Outputs main microphone (HM-132)
select signal to the analog swtich
(IC4) while intercom operation.
Outputs the T5 regulator (MAIN unit;
Q24, Q25) control signal.
High: While transmitting
Outputs the R5 regulator (MAIN unit;
Q22, Q23) control signal.
High: While receiving.
4-7-2 I/O EXPANDER IC (LOGIC BOARD; IC3)