4-5 PORT ALLOCATIONS
4-5-1 CPU (MAIN UNIT; IC19)
4-5-2 SUB-CPU (CONTROL UNIT; IC10)
Outputs reset signal for the LCD con-
troller (IC8).
Input port for serial signal from the
main-CPU (MAIN unit; IC19)
Output port for serial signal to the
main-CPU (MAIN unit; IC19)
Squelch/volume setting level input
ports for VHF band.
Squelch/volume setting level input
ports for UHF band.
Input ports for the up/down signals
from the VHF main dial.
Input ports for the up/down signals
from the VHF main dial.
Outputs brightness control signal for
the display backlight.
Outputs control signal for the contrast
of display.
5
10
11
59, 60
61, 62
73, 74
75, 76
77
79
LRES
TXD
RXD
VSQLV,
VVOLV
USQLV,
UVOLV
VDLA,
VDLB
VDLA,
VDLB
BRITV
CONTV
4 - 6
Input port for the decoded CTCSS sig-
nals.
Input ports for the CPU system clock
oscillator (X4: 10.000 MHz).
Input port for the reset signal.
I/O port for the cloning signal.
Outputs strobe signals for the PLL IC
(IC2).
Outputs strobe signals for the D/A con-
vertor (IC3).
Outputs serial clock signal for the PLL
IC (IC2) and D/A convertor (IC3).
Outputs serial data signals for the PLL
IC (IC2) and D/A convertor (IC3).
Input port for serial signal from the
sub-CPU (CONTROL unit; IC10)
Output port for serial signal to the sub-
CPU (CONTROL unit; IC10)
Outputs clock signal for the EEPROM
IC (IC17).
Input port for serial signal from the
EEPROM IC (IC17).
Outputs data signal for the EEPROM
IC (IC17).
Outputs chip select signal for the EEP-
ROM IC (IC17).
Input port for microphone serial signal
via the MDATA controller (IC24).
Input port to detect remote microphon
connection.
Low : HM-90/98 is connected.
Outputs 1750 Hz Europe tone signal.
Outputs power switching circuit (Q74,
Q75) control signal.
High : While turning power ON.
Outputs serial clock signal for the elec-
tronic volume IC (IC10).
Outputs data signal for the electronic
volume IC (IC10).
Input port for packet PTT signal.
High : Packet PTT switch is ON.
Input port for the PTT switch.
High : While PTT switch is pushed.
PLL unlock signal input port for VHF
band.
High : PLL unlock on VHF band.
PLL unlock signal input port for UHF
band.
High : PLL unlock on UHF band.
Outputs control signal for the V-BIAS
selector (Q34, Q35).
High : While receiving on VHF band.
Output control signal for the U-BIAS
selector (Q34, Q36).
High : While receiving on UHF band.
Outputs Rx/Tx pass-bandwidth control
signal.
High : While narrow bandwidth is
selected. ([EUR], [ITA] only)
1
7, 8
9
11
12
13
14
15
16
17
19
20
21
22
23
24
25
26
34
35
44
45
46
47
52
54
59
TONEIN
OSC1,
OSC2
RES
CLONEC
PLSTB
STB
CK
DATA
RXD
TXD
ESCK
ESI
ESO
ECS
MICIN
EXTMIC
ETONE
PCTRL
VCK
VDATA
PTTP1
PTTM1
VUNLK
UUNLK
1RX
4RX
W/N
Pin
Port
Description
number
name
Outputs transmit signal for VHF band.
High : While transmitting on VHF
band.
Outputs transmit signal for UHF band.
High : While transmitting on UHF
band.
Outputs MIC mute control signal.
Low : While DTMF signals are out-
put, etc.
Output ports for output power control
signal.
Outputs cooling fan control signal.
High : While transmitting or after
transmission for 2 minute.
Outputs mute control signal for UHF
AF signals.
High : While UHF squelch is activate.
Outputs mute control signal for VHF
AF signals.
High : While VHF squelch is activate.
Outputs mute control signal for UHF
demodulated signals.
High : While UHF demodulated sig-
nals are muted.
Outputs mute control signal for VHF
demodulated signals.
High : While VHF demodulated sig-
nals are muted.
Input port for detection signal from the
DTMF unit.
Low : While DTMF unit is connected.
Input ports for the decoded DTMF sig-
nal from the DTMF unit.
Outputs CTCSS signals.
Outputs DTMF signals.
60
61
64
68–75
78
79
80
81
82
83
85–85
90
91
VTX
UTX
MMUTE
POWC0–
POWC7
FUNK
UAMUTE
VAMUTE
UDMUTE
VDMUTE
OPD
Q1–Q4
CTCSS
DTMF
Pin
Port
Description
number
name
Pin
Port
Description
number
name
