Icom IC-2710H Service Manual page 12

CPU (MAIN UNIT)
Port
Pin
number name
Input port for tone squelch detector.
"Low" : A matched tone signal is
TSO LB
46
Outputs strobe signal for VHF PLL
48 VSTBPL
circuit.
Input port for VHF PLL unlock signal.
49 VUNLK
Outputs strobe signal for UHF PLL
50 USTBPL
circuit.
Input port for UHF PLL unlock signal.
51 UUNLK
wcov
Outputs VHF VCO switch control
52
signal.
wcos
Outputs shift signal for VHF VCO
53
circuit.
uvcov
Outputs UHF VCO switch control
54
signal.
Outputs shift si F nal for UHF VCO
55 UV COS
circuit.
Outputs transmit signal for VHF band.
"High": While transmitting on VHF
56 VTX
Outputs transmit signal for UHF band.
"High" : While transmitting on UHF
UTX
57
Outputs cooling fan control signal.
"High" : While cooling fan is
58 FANC
Output port for the power switch
control circuit (MAIN unit 03, 04).
75 PCTRL
"High" : Power is turned ON.
Outputs mute control signal for VHF
demodulated signals.
76 VD MUTE
"Low" : VHF demodulated signals
Outputs mute control signal for UHF
demodulated signals.
77 UDMUTE
"Low" : UHF demodulated signals
Outputs mute control signal for VHF
AF signals.
7 8 VAMUTE
"High" : VHF AF signals are
Outputs mute control signal for UHF
AF signals.
79 UAMUTE
"High" : UHF AF signals are
Outputs microphone mute signal.
83 MMUTE "High" : Microphone audio is
Description
received.
band.
band.
activated.
are muted.
are muted.
muted.
muted.
muted.
4 - 6
CPU (MAIN UNIT)
Pin Port
number
name
Input port for differentiated signal
from an optional UT-49.
84 StD
"High": When a correct DTMF
Input ports for DTMF decode signal
85-88 01-04
cress
(BITO-BIT3) from an optional UT-49.
Outputs CTCSS tone signals.
90
Outputs DTMF signals while
transmitting, beep audio while
91 DTMFE
receiving.
Input port for VHF S-meter signal.
94 VSM
Input port for VHF noise signal.
95 VSOLS
Input port for UHF S-meter signal.
96 USM
Input port for UHF noise signal.
97 USO LS
Input port for up/down signal from a
MU/D
98
microphone.
Input port for PTT switch.
99 PTT
SUB-CPU (CONTROL UNIT)
4-5-2
Pin Port
number name
Outputs dimmer control signal.
10 DIMMER
Outputs LCD ON/OFF control signal.
17 LINH
"High": LCD ON
Output port for serial signal to the
19 RDATA
CPU (MAIN unit IC29}.
Input port for serial signal from the
20 TDATA
CPU (MAIN unit IC29}.
Input port for reset signal.
25 RESET
Outputs serial data for the LCD
26 LOI
(CONTROL unit DS4).
Outputs serial clock for the LCD
27
LCL
(CONTROL unit DS4).
Input ports for LCD bias voltage.
78-80 VL1-VL3
Description
signal is received.
Description