Icom IC-E90 Service Manual page 16

4-5-3 CPU (LOGIC UNIT; IC1)
Pin Port
number name
Input port for the PA's temperature
1 PATMP
while transmitting.
3 SD Input port for the S-meter signal.
Input port for the battery voltage divide
5 CHG
signal.
Input port for the power supply voltage
6 VIN
divide signal.
Input port for the CTCSS decorded
7 CTCIN
signal (67.0–254.1 Hz analog signal).
Outputs the FM or WFM regulator
12 WFM control signal.
Low: FM or WFM mode is selected.
Outputs the AM mode regulator con-
13 AM trol signal.
Low: AM mode is selected.
14 CLSFT Outputs the clock shift control signal.
Input port for the CPU reset signal.
19 RESET
High: The CPU is reset.
Input port for the [POWER] switch.
25 POWER
Low: Power is ON.
Input port for the external power sup-
ply connecting signal.
26 CPUHV
Low: While the external power sup-
Outputs the expander IC (AF unit;
28 IOSTB
IC51, pin 1) strobe signal.
Outputs strobe signals to the D/A IC
29 DASTB
(RF unit; IC251, pin 2).
30 CLIN Input port for the cloning signal.
31 CLOUT Output port for the cloning signal.
I/O port for the PLL IC (VCO unit;
IC201, pin 7) data signal.
33 PDAUL
Low: PLL is unlocked.
High: PLL is locked.
Outputs clock signals to the R3V
switch (AF unit; IC51, pin 3), D/A IC
34 CK
(RF unit; IC251, pin 3) and PLL IC
(VCO unit; IC201, pin 4).
35 PLSTB Outputs the PLL IC strobe signal.
40 ECK Outputs the EEPROM clock signal.
Outputs the battery charger control
42 CHGC
signal.
Outputs the +3C regulator control sig-
43 PCON
nal.
Outputs the R3C regulator control sig-
44 R3C nal.
Low: While receiving.
Outputs the T5V regulator control sig-
45 TXC nal.
High: While transmitting.
Description
ply is connected.
Pin Port
number name
46 MICC
47 NOISE
48 MUTE
49 AFON
51 BUSYL
52 GLED
53 RLED
54 LCDL
55 V3C
56 DIUD
57 DICK
58–61 KS3–KS0
62–65 I3–I0
66–69 KR3–KR1
70 V1C
71 VOLDN
72 VOLUP
73 SQL
74 430M
75 144M
77 PTT
81 V2C
82 VSFT
4 - 8
Description
Outputs the mic amplifier regulator
control signal.
Input port for the SQL detection noise
signal.
Outputs mute control signal.
High: AF muting while receiving.
MIC muting while transmitting.
Output AF amplifier regulator control
signal.
Outputs BUSY LED control signal.
High: The BUSY LED is ON.
Outputs key backlight control signal.
High: Green backlight is ON.
Outputs key backlight control signal.
High: Red backlight is ON.
Outputs LCD backlight control signal.
Low: Lights ON.
Outputs the 430 MHz VCO regulator
control signal.
Low: 430 MHz is selected.
Input port for the up/down signal from
the main dial (AF unit; S251).
Output ports for key matrix.
Output ports for Initial matrix.
Input ports for key matrix.
Outputs the 50 MHz VCO regulator
control signal.
Low: 50 MHz is selected.
Input port for the volume level control
signal.
Low: Volume level is low.
Input port for the volume level control
signal.
Low: Volume level is high.
Input port for the [SQL] switch.
Low: While [SQL] switch is pushed.
Outputs the 430 MHz modulation cir-
cuit control signal.
Low: While 430 MHz is transmitting.
Outputs the 144 MHz modulation cir-
cuit control signal.
Low: While 144 MHz is transmitting.
Input port for the [PTT] switch.
High: While [PTT] switch is pushed.
Outputs 144 MHz VCO regulator con-
trol signal.
Low: 144 MHz is selected.
Outputs the VCO select signal.