Port Allocations - Icom IC-A23 Service Manual

4-5 PORT ALLOCATIONS

4-5-1 CPU (LOGIC UNIT; IC1)
Pin Port
number name
Input port for the battely voltage
1 VIN
detection.
Input port for the VOR signal detec-
2 VORD
tion.
3 RSSI Input port for the receive signal level.
Input port for the power detection of
4 RFDETV
power amplifier (RF unit; Q2).
Input port for the transceiver's internal
5 THRMC
temperature.
Input port for the battely type detec-
6 SBATT
tion.
Outputs data signals to the PLL IC (RF
7 PDATA
unit; IC3).
8 PCK Outputs clock signal to the PLL IC.
9 PSTB Outputs strobe signals to the PLL IC.
10 BEEP Outputs beep audio signals.
11 VORS Input port for the 30 Hz phase signal.
12, DICK,
Input port for [DIAL].
21 DIUD
17 LIGHT Input port for [LIGHT] switch.
Outputs the bias control signal for a
18 BPCPI
type of battery.
19 CLOUT Outputs the cloning signal.
20 CLIN Input port for the cloning signal.
Input port for the VOR 30 Hz standard
22 VORC
signal.
23 POWER Input port for [POWER] swtich.
Input port for the [PTT] swtich.
24 PTT
High: While [PTT] switch is pushed.
Input port for the external SP jack con-
nection detection.
25 JACKDET
High: While the external SP jack is
Input port for the external DC connec-
32 DCC
tion detection.
33 RESET Input port for the CPU reset signal.
• Input port for the data signals from
the EEPROM (LOGIC unit; IC7).
47 EDATA
• Outputs data signals to the EEP-
ROM IC.
Input port for the PLL unlock signal.
48 UNLK
Low: PLL is unlocked.
Outputs control signal for the 5V regu-
54 PCON
lator.
Outputs clock signal to the EEPROM
55 ECK
IC (LOGIC unit; IC7).
Description
connected.
4-5-2 SHIFT RESISTOR (RF UNIT; IC5)
Pin Port
number name
5 DETMITE
7 R5C
11 WXC
12 ANLC
13 EMBI
14 AFC
4-5-3 SHIFT RESISTOR (LOGIC UNIT; IC8)
Pin Port
number name
4 VORON
5 PLAYC
6 RECC
7 LIGHTC
11 BLEDC
12 MMUTE
13 ALCC
4 - 6
Description
Outputs detector mute signal to the
AM/FM select switch (IC2, pin 2).
Outputs receiver 5V control signal to
the RX controller (Q20).
Outputs AM/FM (WX ch) select signal
to the RX shift circuit (Q34, D25) and
AM/FM select switch (IC2, pin 5).
Outputs control sigal to the ANL switch
(Q21).
Outputs control signal to the external
microphone controller (Q25, Q26,
D23, D27).
Outputs control signal to the AF out
cotnroller (Q35, Q36) for the AF power
amplifier (IC6).
Description
Outputs control signal to the VOR
controller (Q15).
Outputs playback control signal to the
voice rec/play IC (IC15, pin 23).
Outputs recording control signal to the
voice rec/play IC (IC15, pin 27).
Outputs LCD backlight control signal.
Outputs BUSY LED control signal.
Outputs control signal to the Mic mute
switch (Q12) for internal microphone.
Outputs control signal to the ALC con-
troller (Q11).