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31
HCD-EP50
6-15.
IC PIN FUNCTION DESCRIPTION
•
DISPLAY BOARD IC301
µ
PD78064GF-187-3BA (SYSTEM CONTROLLER, LIQUID CRYSTAL DISPLAY DRIVER)
Pin No.
Pin Name
I/O
Description
1
GENERALDOUT
O
Serial data output to the FM/AM PLL (U2), LC75392 (U6) and 94HC4094 (U15)
2
GENERALCLK
O
Serial data transfer clock signal output to the FM/AM PLL (U2), LC75392 (U6) and 94HC4094
(U15)
3
I2CDATA
I/O
Two-way data bus with the EEPROM (IC302)
4
STEREO
I
FM stereo detection signal input from the LA1837 (U1) “L”: stereo
5
I2CCLK
O
Clock signal output to the EEPROM (IC302)
6
IC
—
Internal connection terminal (connected to ground)
7
X2
O
Main system clock output terminal (4.194304 MHz)
8
X1
I
Main system clock input terminal (4.194304 MHz)
9
VDD
—
Power supply terminal
10
XT1
I
Sub system clock input terminal (32.768 kHz) Not used (open)
11
XT2
O
Sub system clock output terminal (32.768 kHz) Not used (open)
12
RESET
I
System reset signal input from the reset signal generator (IC304) “L”: reset
For several hundreds msec. after the power supply rises, “L” is input, then it changes to “H”
13
REMOTE
I
Remote control signal input from the remote control receiver (X302)
14
PWRFAIL
I
Power failure detection signal input terminal “L”: power failure, “H”: power on
15
RDSCLK
I
Serial data transfer clock signal input from the RDS decoder (IC305)
(Used for the AEP, UK models)
16
CDCLK
I
Serial data transfer clock signal input from the CD block
17
SENSORB
I
Tape sensor input terminal Not used (open)
18
SENSORA
I
Tape play/rec detect sensor input terminal “L” input when the tape play/rec detect
19
CD DOOR SW
I
CD lid open/close detect switch (SW300) input terminal “L”: CD lid is closed
20 to 23 CDIN2 to CDIN5
I
Not used (open)
24
AMS
I
Whether a music is present or not from BA335 (U14) is detected at auto music sensor
“L”: music is not present, “H”: music is present
25
ENCODERA
I
Jog dial pulse input from the rotary encoder (X303 VOLUME) (A phase input)
26
ENCODERB
I
Jog dial pulse input from the rotary encoder (X303 VOLUME) (B phase input)
27
AVSS
—
Ground terminal
28
KEY1
I
Key input terminal (A/D input) SW301 to SW305 (I/
1
, TUNER, TAPE, CD, PLAY MODE
RDS/DIR) keys input (RDS: used for the AEP, UK models)
29
KEY2
I
Key input terminal (A/D input)
SW306 to SW309 (
x
,
X
,
Y
, TUNER MEM ENTER) keys input
30
KEY3
I
Key input terminal (A/D input) SW310 to SW312 (/–, DISPLAY) keys input
31
KEY4
I
Key input terminal (A/D input)
SW313 to SW315 (TUNING –
.
m
,
M
>
, MUSIC MENU) keys input
32
KEY5
I
Key input terminal (A/D input) SW316, SW317 (MEGA BASS,
z
) keys input
33
ANALYZER
I
Analyzer level detection signal input terminal (A/D input) Not used (open)
34
TUNED
I
Tuning detection signal input from the LA1837 (U1) (A/D input) “L”: tuned
35
RDSDATA
I
Serial data input from the RDS decoder (IC305) (Used for the AEP, UK models)
36
AVDD
—
Power supply terminal
37
AVREF
I
Reference voltage input terminal
38, 39
CDOUT1, CDOUT2
O
Not used (open)
40
VSS
—
Ground terminal
41
CDOUT3
O
Not used (open)
42
CDDATA
I/O
Two-way data bus with the CD block
43
CDRESET
O
Reset signal output to the CD block “L”: reset