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IC PIN FUNCTION DESCRIPTION
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MAIN BOARD IC501 M30622MA-A07FP (SYSTEM CONTROLLER (CD MECHANISM CONTROL))
Pin No.
Pin Name
I/O
Description
1
STK-MUTE
O
Power amplifier on/off selection signal output terminal “L”: standby mode, “H”: on
2
POWER
O
Power on/off control signal output for the audio system (+5V) and deck, panel, audio system
(+7V) “L”: standby mode, “H”: power on
3
F-RELAY
O
Relay drive signal output for the speaker protect “H”: relay on
4
R-RELAY
O
Relay drive signal output for the speaker protect “H”: relay on Not used (open)
5
CD-POWER
O
Power on/off control signal output for the CD mechanism deck section
“L”: standby mode, “H”: power on
6
LINE-MUTE
O
Line muting on/off control signal output terminal “L”: muting on
7
DBFB-H/L
O
DBFB normal/high selection signal output to the M62493FP (IC101)
“L”: DBFB high, “H”: DBFB low
8
BYTE
I
External data bus line byte selection signal input terminal Fixed at “L” in this set
9
CNVSS
—
Ground terminal
10
XC-IN
I
Sub system clock input terminal (32.768 kHz)
11
XC-OUT
O
Sub system clock output terminal (32.768 kHz)
12
RESET
I
System reset signal input from the reset signal generator (IC502) “L”: reset
For several hundreds msec. after the power supply rises, “L” is input, then it changes to “H”
13
X-OUT
O
Main system clock output terminal (16 MHz)
14
VSS
—
Ground terminal
15
X-IN
I
Main system clock input terminal (16 MHz)
16
VCC
—
Power supply terminal (+5V)
17
NMI
I
Non-maskable interrupt input terminal Fixed at “H” in this set
18
WAKE UP
I
Wakeup control signal input from the fluorescent indicator tube driver (IC601) “H” active
19
SCOR
I
Subcode sync (S0+S1) detection signal input from the CXD2587Q (IC101) on the CD block
20
RDS-INT
I
RDS serial data transfer clock signal input from the FM/AM tuner unit (Used for the AEP, UK,
German and North European models only)
21
RDS-DATA
I
RDS serial data input from the FM/AM tuner unit (Used for the AEP, UK, German and North
European models only)
22
AC-CUT
I
AC off detection signal input from the reset signal generator (IC502) “L”: AC cut checked
23
PL-CLK
O
Serial data transfer clock signal output to the pro-logic circuit Not used (open)
24
PL-DATA
O
Serial data output to the pro-logic circuit Not used (open)
25
PL-LAT
O
Serial data latch pulse output to the pro-logic circuit Not used (open)
26
TIMER LED
O
LED drive signal output of the TIMER SELECT indicator (D636) “H”: LED on
27
PROTECTOR
I
Protect on/off detection signal input from the speaker protect circuit
“L”: protect on, “H”: protect off
28
V MUTE
O
Muting on/off control signal output terminal “L”: muting off Not used (open)
29
IIC-CLK
I/O
Communication data reading clock signal input or transfer clock signal output with the fluo-
rescent indicator tube driver (IC601)
30
IIC-DATA
I/O
Communication data bus with the fluorescent indicator tube driver (IC601)
31
NCO
O
Not used (open)
32
SQ-DATA
I
Subcode Q data input from the CXD2587Q (IC101) on the CD block
33
SQ-CLK
O
Subcode Q data reading clock signal output to the CXD2587Q (IC101) on the CD block
34
SW MODE
O
Not used (open)
35
CD-DATA
O
Serial data output to the CXD2587Q (IC101) on the CD block
36
RY-SW
I
Connection detect signal input of the headphone jack (J701)
“L”: no connected, “H”: headphone connected
37
CD-CLK
O
Serial data transfer clock signal output to the CXD2587Q (IC101) on the CD block
38
493-LATCH
O
Serial data latch pulse output to the M62493FP (IC101)