5 - 9
Pin
No.
Port
Name
Description
1
BLED
Outputs TX/RX indicator (DS201) control
signal to the TX/RX LED driver (Q201).
“High”=While the squelch is open.
2
LIGHT
Outputs backlight control signal to the
backlight LEDs driver (Q203).
“High”=While backlight is ON.
3–7
KR0–KR4
Input ports for keypad.
8
POWER
Input port for [PWR] key (S1).
“Low”=When the key is pushed.
9
BATT
Outputs power supply line select signal to the
DC switch (IC50, Q35).
10
ESIO
I/O port for data signal from the EEPROM
(IC51).
11
ECK
Outputs clock signal to the EEPROM (IC51).
13–
17
KS0–KS3
Input ports for keypad.
22
PTT
Input port for [PTT] key (MAIN UNIT; S701).
“High”=While the key is pushed.
23
SQL
Input port for [SQL] key (MAIN UNIT; S700).
“Low”=While the key is pushed.
24, 5 DICK, DIUD Input ports for [DIAL] (MAIN UNIT; S702).
26
ANOIS
Input port for noise signal from the A_BAND
IF IC (MAIN UNIT; IC100).
27
DTCS
Outputs tone filter passband control signal
to the tone filter (R337–R340, C338–C341)
switch (Q307).
“High”=During mode operation.
28
BNOIS
Input port for noise signal from the B_BAND
IF IC (MAIN UNIT; IC200).
29
IOSTB1
Outputs strobe signal to the D/A converter (RF
UNIT; IC951).
30
DATA
Outputs common data signal to the D/A
converters (LOGIC UNIT; IC303, MAIN UNIT;
IC702, RF UNIT; IC951).
31
AMBETXD
†
Outputs AME TX data to the attached UT-121
(CODEC UNIT for IC-91AD).
32
AMBERXD
†
Input por ts for AME RX data from the
attached UT-121 (CODEC UNIT for IC-91AD).
33
CK
Outputs common clock signal to the D/A
converters (LOGIC UNIT; IC303, MAIN UNIT;
IC702, RF UNIT; IC951).
34
DASTB1
Outputs strobe signal to the D/A converter (RF
UNIT; IC950).
35
DASTB2
Outputs strobe signal to the D/A converter
(IC303).
36
CHGC
Outputs charge control signal to the charger
circuit (Q150, Q153, D150, D152).
“High”=While charging.
37
CHGH
Outputs charging current control signal to the
charger circuit (Q150, Q153, D150, D152).
“High”=When the charging is completed.
38
CPUHV
Inputs HV line detection signal from the HV
line voltage detector (Q51, D52).
“Low”=While no exrternal DC power supply is
connected.
39
PCON
Outputs power control signal to the +3V
regulator (Q100, Q101, D100).
“Low”=While the transceiver’s power is OFF.
41
MUTE
Outputs TX mute signal to the mode switch
(IC301).
“High”=While the transmitting is muted.
43
CTCOUT
Outputs CTCSS/DTCS signals.
5-6 CPU PORT ALLOCATION
Line
Description
HV
The same voltage as the connected external
power supply thrugh the external DC IN jack (RF
UNIT; J1000).
VCC
The same voltage as the attached battery pack
passed through the DC switch (RF UNIT; Q1000,
D1000, D1001).
The voltage is applied to the drive amplifi er (RF
UNIT; Q101), power amplifier (RF UNIT; Q100)
and LED driver (LOGIC UNIT; Q202, Q203).
+3CPU
Common 3 V converted from VCC line at the
CPU3 regulator (LOGIC UNIT; IC100).
The converted voltage is applied to the CPU (IC1),
EEPROM (IC51), etc.
+3V
Common 3 V converted from +3CPU line at the
+3V regulator (Q100, Q101, D100).
The converted voltage is applied to the PLL IC
(RF UNIT; IC800), D/A converters (MAIN UNIT;
IC701, IC702), etc.
RFR3
Rceive 3 V controlled by RFR3 regulator (Q602,
Q603) using
“
R3C
”
signal from the expand IC
(MAIN UNIT; IC701, pin 14), controlled by strobe
signal "IOSTB3" from the CPU (LOGIC UNIT;
IC1, pin 87).
The voltage is applied to the RF circuits (RF UNIT).
T5
Transmit 5 V controlled by T5 regulator (Q650–Q652)
using
“
TXC
”
signal from the CPU (IC1, pin 99).
The controlled voltage is applied to the APC ampli-
fi er (IC150), pre-driver (Q102), etc.
VCO3V
Common 3 V converted from VCC line at the
VCO3V regulator (Q800, Q801, D800, D801).
The voltage is applied to the VCO regulators.
BCVCO3
Rceive 3 V controlled by BCVCO3 regulator (RF
UNIT; Q801) using
“
BCVCOC" signal from the
expander (RF UNIT; IC951, pin 5), controlled by
“
IOSTB1
”
signal from the CPU (IC1, pin 29).
The controlled voltage is applied to the BC BAND
VCO (
VCO UNIT; Q1, D1, D3, D5).
VVCO3
Common 3 V controlled by VVCO3 regulator
(Q800) using
“
VAVCOC
”
signal from the expander
(IC951, pin 6), controlled by the
“
IOSTB1
”
from the
CPU (LOGIC UNIT; IC1, pin 29).
The controlled voltage is applied to the VHF BAND
VCO
(VCO UNIT; Q51, D51, D54, D55).
UVCO3
Common 3 V controlled by VVCO3 regulator
(Q800) using
“
UAVCOC
”
signal from the expander
(IC951, pin 7), controlled by the
“
IOSTB1
”
from the
CPU (LOGIC UNIT; IC1, pin 29).
The controlled voltage is applied to the UHF BAND
VCO
(VCO UNIT; Q101, D100, D101, D104).
+5.5V
Common 5.5 V boosted at the DC-DC up-con-
verter (IC101, D101).
The boosted voltage is applied to the PLL IC (RF
UNIT; IC800), PLL IC (MAIN UNIT; IC400), refer-
ence oscilator (X450), etc.
5-5 POWER SUPPLY CIRCUITS (LOGIC UNIT)
†
Available when the optional UT-121 is installed.
