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HCD-GX255/RG170/RG470
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IC Pin Function Description
MAIN BOARD IC901 M30302MCP-A02FPU0 (SYSTEM CONTROLLER)
Pin No.
Pin Name
I/O
Description
1
O-BD3401-
DATA
O
Serial data output to the electrical volume
2
O-BD3401-CLK
O
Serial data transfer clock signal output to the electrical volume
3
O-VFD-RESET
O
System reset signal output to the FL/LED driver
4
O-VFD-CE
O
Chip enable signal output to the FL/LED driver
5
I-AC-CUT
I
AC power detection signal input terminal
6
I-VOL-A
I
Jog dial pulse input terminal
7
I-SIRCS-IN
I
SIRCS signal input terminal
8
BYTE
I
Mode setting terminal Normally not used
9
CNVSS
I
Mode setting terminal Normally not used
10
XCIN
(32.768KHZ)
I
Sub system clock input terminal (32.768 kHz)
11
XCOUT
(32.768KHZ)
O
Sub system clock output terminal (32.768 kHz)
12
I-RESET
I
System reset signal input from the reset signal generator "L": reset
For several hundreds msec. after the power supply rises, "L" is input, then it changes to "H"
13
XOUT (16MHZ)
O
Main system clock output terminal (16 MHz)
14
VSS
-
Ground terminal
15
XIN (16MHZ)
I
Main system clock input terminal (16 MHz)
16
VCC1
-
Power supply terminal (+3.3V)
17
NMI
I
Non-maskable interrupt signal input terminal
18
I-RDS-CLK
I
RDS data transfer clock signal input terminal (AEP, East European models)
19
I-SCOR
I
Subcode Q sync (SCOR) input from the CD DSP
20
I-AC-PULSE
I
AC main power detection signal input terminal
21
I-VOL-B
I
Jog dial pulse input terminal
22
O-STBY-LED
O
LED drive signal output terminal
23
O-SYS-MUTE
O
Muting on/off control signal output terminal
24
O-STK-MUTE
O
Standby signal output to the power amplifier (for front speaker output)
25
O-SWR
O
Relay drive signal output for surround output Not used
26
O-POWER-
RELAY
O
Relay drive signal output for main power
27
O-FRONT-SP-
RELAY
O
Power on/off control signal output for the fan motor and amplifier section
28
O-MP3-CLK
O
Serial data transfer clock signal output to the MP3 decoder
29
I-MP3-DI
I
Serial data input from the MP3 decoder
30
O-MP3-DATA
O
Serial data output to the MP3 decoder
31
O-CD-DATA
O
Serial data output to the CD DSP
32
I-CD-SENS
I
Internal status (SENSE) input from the CD DSP
33
O-CD-CLK
O
Serial data transfer clock signal output to the CD DSP
34
O-XTCN
O
Oscillator control signal output to the CD DSP
35
O-VFD-DATA
O
Serial data output to the FL/LED driver
36
I-VFD-DATA
I
Serial data input from the FL/LED driver
37
O-VFD-CLK
O
Serial data transfer clock signal output to the FL/LED driver
38
O-MP3-RESET
O
System reset signal output to the MP3 decoder
39
O-MP3-CS
O
Chip select signal output to the MP3 decoder
40
I-MP3-ACK
I
Acknowledge signal input from the MP3 decoder
41
xHOLD
I/O
Not used
Summary of Contents for HCD-GX255
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