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4 - 4
4-5 PORT ALLOCATIONS
4-5-1 CPU (IC661)
LINE
DESCRIPTION
VCC
The voltage from the connected DC power
supply passed through the [VOL] switch (R1:
VR BOARD).
CPU5V
5V for the CPU (IC661) converted from the
VCC line at the CPU5V regulator circuit (IC551).
M5V
Common 5V line converted from the VCC line
at the M5V regulator circuit (Q551–Q553).
T5V
5V for the transmit circuits controlled by the
T5V control circuit (Q323) using the T5VS
signal from the CPU (IC661, pin 90).
S5V
5V for the AF circuits controlled by the S5V
control circuit (Q561) using the S5VS signal
from the CPU (IC661, pin 87).
R5V
5V for the receive circuits controlled by the R5V
controll circuit (Q322) using the R5VS signal
from CPU (IC661, pin 89).
4-4 POWER SUPPLY CIRCUITS
4-4-1 VOLTAGE LINES
PIN
NUMBER
PORT
NAME
DESCRIPTION
1
BEEP
Output port for BEEP signal.
3
EXSTB
Output port for external expander
strobe signal.
4
DASTB
Output port for external D/A strobe
signal.
5
PLSTB
Output port for PLL strobe.
6
ERXDI
Input port for cloning.
7
ETXDO
Output port for cloning.
10
SDATA
Output port for serial data.
11
SCK
Output port for serial clock.
12
ESCK
Input port for EEPROM clock.
13
ESDA
I/O port for EEPROM data.
14
TLED
Output port for TX LED driver.
15
RLED
Output port for RX LED driver.
17
CSIFT
Output port for clock shift signal.
25
RESET
Input port for reset signal.
27
WDECV
Input port for WX tone signal.
28
EXDET
Input port for the [MIC/SP] detect
signal.
29
VOXT
Input port for VOX signal.
30
BATTV
Input por t for batter y voltage
detection signal.
31
TDETV
Input port for TX power level.
32
NOISV
Input port for noise level.
33
RSSIV
Input port for RSSI level.
34
LOINV
Input port for PLL lock voltage level.
35
TEMPV
Input port for temperture level.
75, 76
CONT1, CONT2
Output ports for LCD contrast
control signal.
PIN
NUMBER
PORT
NAME
DESCRIPTION
77, 78
LEDS1, LEDS2
Output port for dimmer control
signal.
80
MICMS
Output port for microphone mute
signal.
"HIGH": Microphone mute
81
ISPMS
Output port for internal speaker
mute signal.
"HIGH": Speaker mute
84
AFMS
Output port for AF mute signal.
85
AFVS
Output port for AF amplifier power
supply control signal.
102
PTTIN
Input port for [PTT] switch.
103
EXPTT
Input port for external PTT switch.
104
BTYPE
I n p u t p o r t fo r b a t t e r y t y p e
detection.
105
PTTM
Output port for microphone mute
signal.
106–108
MIC1–MIC3
Output por ts for microphone
sensitivity detection signal.
109
SQL
Input port for [SQL] key.
110
UP
Input port for [
Y
] key.
111
DOWN
Input port for [
Z
] key.
112
CH/WX
Input port for [CALL] key.
113
16/9
Input port for [16] key.
114
SCAN
Input port for [CH] key.
115
H/L
Input port for [Hi/Lo] key.
117
VOXM
Ouput port for mute signal in VOX
mode.
119
UNLK
Input port for PLL unlock signal.
PIN
NUMBER
PORT
NAME
DESCRIPTION
6
DETMS
Output port for DET mute signal.
11
ATTS
Output port for RF attenuator control
signal.
12
TXMS
Output port for TX mute signal.
13
VCOS
TX/RX VCO switching signal.
14
SQLT
Output port for squelch control signal.
4-5-2 EXPANDER (IC341)