Cpu Port Allocations - Icom IC-F3 Service Manual

4-5 CPU PORT ALLOCATIONS

4-5-1 CPU (IC8)
Pin Port
number name
Input port for CTCSS/DTCS signals
1 CTCIN
for decoding.
Outputs reference oscillator for the
11 CSIFT
CPU control signal.
Outputs clock signal to the PLL IC
12 SCK
(IC1), EEPROM (IC7) and expander
IC (IC10), etc.
Input port for the data signals from
13 SI
EEPROM (IC7), etc.
Outputs data signals to the PLL IC
14 SO
(IC1), EEPROM (IC7) and expander
IC (IC10), etc.
Input port for PLL unlock signal from
15 UNLK
the PLL IC (IC1). High level signal is
applied during unlock.
Outputs strobe signals to the PLL IC
18 PLST
(IC1).
Input port for noise signals (pulse
19 NOIS
type) from the FM IF IC (IC2).
Outputs LCD contrast control signal.
26 CONT
High: When normal level is selected
36–41
KS0–KS5
(IC-F3/S)
Output ports for key matrix.
40, 41
KS4, KS5
(IC-F4/S)
Outputs mic. mute control signal.
42 MM
Low: When DTMF or 2/5-tone sig-
Outputs RX mute control signal.
43 RM
Low: When muted
44–47 KR0–KR5 Input ports for key matrix.
Outputs R5 regulator control signal.
48 R5C
Low: While receiving
Outputs S5 regulator control signal.
49 S5C
Low: While power is ON
Outputs T5 regulator control signal.
50 TXC
Low: While transmitting
Outputs T5 regulator control signal.
51 T5C
Low: While transmitting
Outputs LCD backlight control signal.
52 LIGHT
High: Lights ON
Outputs the regulator circuit for the
53 AFON
AF amplifier control signal.
High: While AF amp. is activated.
Outputs strobe signals to the
54 DST
expander IC (IC10).
CTDA0– Outputs CTCSS and DTCS encode
60–62
CTDA2 signals (3-bit, D/A type).
Outputs filter switch control signal
for the CTCSS and DTCS (Q38).
63 DUSE
High: DTCS is activated.
Description
nal is selected
CPU (IC8) — continued
Port
Pin
name
number
MTONE
90
DTMF
91
4-5-2 OUTPUT EXPANDER IC (IC10)
Pin Port
number name
2 DST
3 SCK
4 SO
11–13 T1–T3
14 T4
4 - 4
Description
Output port for:
Beep audio while receiving.
2/5-tone signals while transmitting.
Output port for DTMF signals while
transmitting.
Description
Input port for strobe signals.
Input port for clock signal.
Input port for data signal.
Output tuneable bandpass filter
control voltage.
Outputs tuneable bandpass filter
control signal while receiving.
Outputs RF output power control
signals while transmitting.