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4 - 4
4-5 PORT ALLOCATIONS
• CPU (MAIN-A/B/C UNIT: IC35)
Pin
No.
Port
Name
Description
I/O
A3
NWC1
Bandwidth switches (Q27–Q29, D8, D16)
control.
“High”=While operating in the wide mode.
O
B3
DUSE
CTCSS/DTCS switch (Q12) control.
O
B11
CENC0 CTCSS/DTCS tone encode signals.
O
B12
NOIS
Noise signal from the IF IC (IC15).
I
B13
DDST
Strobe signal to the DTMF decode IC (MAIN-A/
B/C UNIT: IC10).
O
C6
ESCL
Serial clock to the EEPROM (IC36).
O
C8
FSDA
Serial data to the expander (FRONT UNIT:
IC702 and IC703).
O
C11
CENC1 CTCSS/DTCS tone encode signals.
O
C12
POSW
Power switch (VR UNIT: R502).
“
Low
”
=While the power is ON.
I
C13
MTCK
Serial clock to the baseband IC (MAIN-A/B/C
UNIT: IC4).
O
C14
DDSD
Serial data to the DTMF decode IC (IC10).
O
D4
NWC2
Bandwidth switches (Q18, D3, D4) control.
“High”= While operating in the narrow or digital
mode.
O
D6
ESDA
Serial data to the EEPROM (IC36).
I/O
D8
FSCL
Serial clock to the expanders (FRONT UNIT:
IC702 and IC703).
O
D11
CENC2 CTCSS/DTCS tone encode signals.
O
D12
DDAC
Serial clock to the DTMF decode IC (IC10).
O
D13
MSCK
Serial clock to the baseband IC (MAIN-A/B/C
UNIT: IC4).
O
D15
CSFT
CPU clock frequency shift control.
“High”=The clock frequency is shifted.
O
E13
RES
CPU reset signal from the reset IC (IC34).
“High”=CPU is reset.
I
K1–
K3
CBI0−2 [ROTARY SELECTOR] (VR UNIT: S501).
I
L1
EMER
[Emer] (VR UNIT: S501).
I
L2
SIDE1
[Side1] (S3).
“
Low
”
=Pushed.
I
L3
CBI3
[ROTARY SELECTOR] (VR UNIT: S501).
I
L4
SIDE2
[Side2] (S2).
“
Low
”
=Pushed.
I
M1
SIDE3
[Side3] (S1).
“
Low
”
=Pushed.
I
M3
TLED
TX indicator (FRONT UNIT: DS710) control.
“High”=While transmitting.
O
M4
S5C
S5V line control.
“
Low
”
=While in the power save mode.
O
M5
PMFM
PM/FM switch (IC13) control.
O
M7
RMUTO
AF mute switch (IC8) control.
“Low”=Mute.
O
M8
SENC
Single tone encode signal.
O
M11
BATV
Battery voltage.
I
M14
IPTT
[PTT] (S4).
“
Low
”
=Pushed.
I
N1
RLED
RX indicator (FRONT UNIT: DS710) control.
“High”=While receiving a signal.
O
N2
UNLK
PLL IC (IC14) unlock detect.
“Low”=Unlocked.
I
N4
PWON
VCC line control.
“
Low
”
=While the power is ON.
O
N5
T5C
T5V line control .
“
Low
”
= While transmitting.
O
N8
BEEP
Beep sound (Square wave).
O
N10
SDEC
Decoded 2/5 tone and DTMF signals.
I
N12
RSSI
RSSI voltage from the IF IC (IC15).
I
P1
SCK
Serial clock to the PLL IC (IC14) and D/A
converter (IC9).
O
Pin
No.
Port
Name
Description
I/O
P2
SSO
Serial data to the PLL IC (IC14) and D/A
converter (IC9).
O
P3
DAST
Strobe signal to the D/A converter (IC9).
O
P4
DASW
Outputs mode (Digital/Analog) switching
control.
“High”=While operating in the analog mode.
O
P5
R5C
R5V line control.
“
Low
”
= While receiving.
O
P6
EMPH
Outputs emphasis characteristic switching
control.
O
P12
LVIN
Lock voltage.
I
R1
TMUT
Transmit mute switch (RF UNIT: Q604) control.
“High”=Mute.
O
R2
DSDA
Serial data to the D/A converter (IC33).
O
R4
PLST
PLL strobe signal to the PLL IC (IC14).
O
R3
MTDT
Serial data to the baseband IC (MAIN-A/B/C
UNIT: IC4).
O
R10
CDEC
CTCSS/DTCS signals.
I
Pin
No.
Port
Name
Description
1
T1
Tuning voltage to the tuned BPF (
D21,D24, L27,
L29, C308, C309, C320, C322, C323,
).
2
T2
• While receiving
Tuning voltage to the tuned BPF (
D17, D18,
L23, L25, C273, C278, C287, C291
).
• While transmitting
TX power setting voltage to the APC AMP (RF
UNIT: IC601).
3
TLVA
Oscillating frequency adjustment voltage to the TX
VCO (
Q32, D9, D12, D13)
.
4
RLVA
Outputs oscillating frequency adjust voltage to the
RX VCO-A/B (
Q30, D10, D14/Q31, D11, D15)
.
Pin
No.
Port
Name
Description
4
AFON
AF power amplifi er (IC705 and IC706) control.
“High”=Activated.
5
LIGH
LCD backlight control.
“High”=While the backlight lights.
6
SPCON
Internal or external speaker select.
“Low”=While the internal speaker is used.
7
MCON
Internal or external microphone select.
“Low”=While the internal microphone is used.
• D/A CONVERTER (MAIN-A/B/C UNIT: IC33)
• EXPAND IC (FRONT UNIT: IC702)