Icom IC-2SET Service Manual page 11

•
OUTPUT PORT
•
OUTPUT EXPANDER
(10
UNIT,
IC2)
PORT
NUMBER
PIN
NUMBER
DESCRIPTION
DO
[LAMPO]
77
Becomes "HIGH" when
the
backlight
LEDs
light up.
D1
[BUSY
LED]
78 Outputs a
signai for iighting
up
in
green the transmit/receive
indicator.
This port
becomes
"LOW"
while
receiving.
(squeich
opens)
D2
[TONE OUT]
79 Outputs a
1750 Hz tone
signai.
(IC-2SET oniy)
D3
[TOE]
80
Outputs an enable
signal for
the
UT-49.
D6-D9
[KEYSO-
KEYS3]
3~6
Outputs a strobe signal for
the
keyboard,
initial
and key matrices
and D/A converter counting signai
alternateiy in
an
intervai.
ROO
[SOK]
15
Outputs ciock signals for serial
data.
R01
[lO
STB]
16
Outputs a
strobe signal
for serial
data to the
expander
ICs.
R02
[SDATA]
17 Outputs
serial
data synchronized
with the
SOK
signal.
R03
[PLL
STB]
18
Outputs a strobe signal for serial
data
to
the
PLL
1C.
•
OUTPUT EXPANDER
(10
UNIT,
IC1)
PORT NUMBER
PIN
NUMBER
DESCRIPTION
Q2,
03
[BA2,
BA3]
5,
6 Outputs a control signal
for
the
RF
bandpass
filter.
05,
06
[POW
1
,
POW2]
13,
14
Outputs a
control signal for
the
output
power
selecting
circuit.
This signal
is
converted
into
PCON
voltage
(APC reference
voltage)
using the
D/A
converter (R2~R6).
PORT
NUMBER
PiN
NUMBER
DESCRiPTiON
01
[AF
ON]
4
Outputs an
AF
mute
signal for
AF
power
amplifier.
02
[MiC
MUTE]
5
Outputs a
microphone mute
signai.
When
transmitting
a tone
signai,
the
MiC
signai
iine
goes
to
ground.
03
[RMUTE]
6 Outputs a receive
mute
signal for
the
AF mute
circuit.
When
emitting
a
beep
tone,
this
port
outputs the
mute
signai
and
the
AF
ON
port
does
not output
it.
04
[TMUTE]
7
Outputs a control signal for
T+5
V
regulator.
05
[SEND]
14
Outputs
transmit/receive switching
signals.
This port
becomes
"LOW"
whiie transmitting.
06
[PSC]
13 This port
becomes "HiGH"
while
the
power
saver function
is
activated.
07
[CPC]
12 Outputs a
controi signai to cut
off
the ioop
fiiter
whiie the
power saver
function
is
activated.
08
[MODE]
11
Outputs a
mode
signai.