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4 - 4
4-5 PORT ALLOCATIONS
• CPU (IC51)
BALL
No.
LINE
NAME
DESCRIPTION
I/O
A5
RXC
Power supply switching control.
H= During receive or stand-by.
O
A6
RMUTE
RX AF mute switch control.
L= D u r i n g t h e s q u e l c h c i r c u i t i s
activated.
O
A7
DMOSI Serial data to the DSP (IC903).
O
A15
PWON
Power supply switching control.
H= The transceiver's power is ON.
O
B12
NOIS
Noise level detect.
H= Squelch close
I
B15
AFON
AF power AMP control.
H= AF power AMP (IC55) is activated.
O
C1,
C2
CBI2,
CBI0
[ROTARY SELECTOR]
input.
I
C5
TXC
Power supply switching control.
H= While transmitting.
O
C8
ESDA EEPROM (IC52) serial data.
I/O
C13
POSW Power switch. (R424)
I
C14
ADS
1st IF filters (FI1 and FI2) switching
control.
L= During digital mode.
O
C15
NWC
Receive mode (narrow/wide) switching.
L= During narrow mode.
O
D2,
D3
CBI3,
CBI1
[ROTARY SELECTOR]
input.
I
D6
DSCK DSP (IC903) clock.
O
D8
ESCL EEPROM (IC52) clock.
O
D13
DPDN
DSP (IC903) power control.
H= DSP is inactivated
O
D14
DRES
DSP (IC903) reset.
L= Reset
O
D15
CSFT
Clock frequency shift.
H= Clock frequency is shifted.
O
E13
RES
CPU reset.
I
H1
SIDE1
[UPPER]
key input.
L= Pushed
I
H2
SIDE2
[LOWER]
key input.
L= Pushed
I
J1
IPTT
Internal
[PTT]
input.
L= Pushed.
I
J2
XPTT
External PTT input.
H= An external PTT is pushed.
I
L1, L2
MCG0,
MCG1
MIC gain control.
O
L12
TLED
Busy LED (Red) control.
L= LED lights (While transmitting)
O
L13
RLED
Busy LED (Green) control.
L= LED lights. (While receiving a signal)
O
L14
SSO
Common serial data.
O
L15
SCK
Common clock.
O
M1
TMUT
Transmission mute.
L= TX inhibit.
O
M2
ATX
Automatic TX control for VOX mode.
H= W h i l e M I C a u d i o f r o m t h e
connected headset is detected.
O
M8
BEEP Beep audio. (Square waves)
O
M11
MDET External connection detect.
I
M14
DAST
AF CUSTOM IC (IC2) strobe.
H= Load enable.
O
BALL
No.
LINE
NAME
DESCRIPTION
I/O
N11
VOXV Microphone input sensing voltage.
I
N12
BATV Battery voltage sensing.
I
N14
DMISO DSP (IC903) serial data.
O
P4
PLSW
PLL lock up time control.
L= Fast lock up
O
P10
TEMP Temperature sensing voltage.
I
P11
RSSI
RSSI sensing voltage.
I
P12
AFVI
[VOLUME CONTROL]
input.
I
P15
DSS
DSP (IC903) chip select.
O
R3
S5C
Power supply line "S5C" switching
control.
H= Supplying current to the TX/RX
common circuits.
O
R4
PLST PLL strobe.
O
R9
MDWN
Man down detect.
L= While the transceiver is horizontal.
I
R10
LVIN
Lock voltage input.
I