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40
41
42
43
46
47
49
50
51
52
53
55
56
57
58
59
61
65
66
67
72
73
80
Outputs strobe signal to the BFO’s
DDS IC (IC9701).
Outputs strobe signal to the DDS IC
(IC9001) for main loop.
Outputs strobe signal to the PLL IC
(IC9101) for main loop.
Outputs strobe signal to the D/A con-
vertor (IC6501).
Input port for the RTTY keying signal.
High : While marking.
Low : While spacing.
Outputs AGC first control signal.
Low : While AGC first is ON.
Outputs FM mode select signal.
High : While FM or FM-N is selected.
Outputs AM mode select signal.
High : While AM or AM-N is selected.
Outputs noise blanker control signal.
High : While noise blanker is ON.
Outputs detecting output select signal.
High : While AM or AM-N is selected.
Outputs detecting output select signal.
High : While FM or FM-N is selected.
Outputs attenuator control signal.
High : While attenuator is ON.
Outputs the pre-amplifier ON/OFF
control signal.
High : While the pre-amplifier is OFF.
Outputs the pre-amplifier ON/OFF
control signal.
High : While the pre-amplifier is ON.
Outputs the speech compressor con-
trol signal.
High : While the speech compressor
is ON.
Outputs 9600 bps packet mode control
signal.
High : While 9600bps packet mode
is ON.
Outputs optional DSP unit control sig-
nal.
High : While the DSP unit is ON.
Outputs the EEPROM clock signal.
I/O port for the EEPROM data signal.
Outputs reset signal.
Input port for the external paddle dash
signal.
Input port for the external paddle dot
signal.
Outputs AF mute control signal.
Low : While AF is muting.
SBST
PDST
PMST
DSTB
FSKK
AGFS
FMS
ANS
NBS
AFS2
AFS1
ATTS
PROS
PRES
COMS
D96S
DSPS
ECK
EDT
DRES
DASK
DOTK
AFMS
(MAIN unit; IC5901)–Continued
Pin
Port
Description
number
name
85
89
90
91
95
98
99
100
Outputs the speaker switching signal.
High : The speaker is ON.
Input port for supplied voltage detect-
ing signal.
Outputs power save control signal.
Low : While power save is ON.
Input port for the microphone
[UP]/[DWON] signal from the rear
panel.
Input port for the CTCSS signal.
Outputs strobe signal to the expander
IC (IC6101, pin 1).
Outputs serial data to the D/A conver-
tor (IC6501, pin 8) and expander IC
(PA unit; IC600, pin 8).
Outputs serial clock to the D/A conver-
tor (IC6501, pin 7) and expander IC
(PA unit; IC600, pin 7).
SPS
VCCL
PSS
MUDL
CTCL
MSTB
MDT
MCK
Pin
Port
Description
number
name
(MAIN unit; IC5901)–Continued