XR-C8220 - Sony Car Audio Service Manual (repair manual). Page 38

– 52 –

Pin No.

Pin Name

I/O

Function

68

SUBCE

O

Chip enable signal output to the sub electrical volume (IC350)    “H” active

69

FLASH-W

I

Internal flash memory data write mode detection signal input terminal    “L”: data write mode
Not used (fixed at “H” in this set)

70

IIC SIO

I/O

Two-way data bus with the external device    Not sued (fixed at “H”)

71

IIC CKO

O

Bus clock signal output to the external device    Not sued (pull-up)

72

RC-IN1

I

Rotary remote commander shift key input terminal    “L”: shift

73

X1A

O

Sub system clock output terminal (32.768 kHz)

74

X0A

I

Sub system clock input terminal (32.768 kHz)

75

DAVN

I

Data transmit completed detect signal input from the RDS decoder    “H” active
Not sued (open)

76

KEYACK

I

Input of acknowledge signal for the key entry    Acknowledge signal is input to accept function 
and eject keys in the power off status    On at input of “H”

77

BU-IN

I

Battery detect signal input from the SONY bus interface (IC602) and battery detect circuit
“L” is input at low voltage

78

ILL IN

I

Auto dimmer control illumination line detection signal input terminal
“L” is input at dimmer detection

79

TEL-ATT

I

Telephone muting signal input terminal    At input of “H”, the signal is attenuated by –20 dB

80

NOSESW

I

Front panel block remove/attach detection switch (SW500) input terminal
“L”: front panel is attached

81

ACC IN

I

Accessory detect signal input terminal    “L”: accessory on

82 to 85

TIR-D0 to TIR-D3

I/O

Two-way data bus with the external device    Not used (open)

86

HSTX

I

Hardware standby input terminal    “L”: hardware standby mode    Reset signal input in this set

87

MD2

I

Setting terminal for the CPU operational mode (fixed at “L” in this set)

88

MD1

I

Setting terminal for the CPU operational mode (fixed at “H” in this set)

89

MD0

I

Setting terminal for the CPU operational mode (fixed at “H” in this set)

90

RESET

I

System reset signal input from the reset signal generator (IC500) and reset switch (SW800)
“L”: reset    “L” is input for several 100 msec after power on, then it changes to “H”

91

VSS

—

Ground terminal

92

X0

I

Main system clock input terminal (3.68 MHz)

93

X1

O

Main system clock output terminal (3.68 MHz)

94

VCC

—

Power supply terminal (+5V)

95

TIR-BUSY

I

Busy detection signal input from the external device    Not used (fixed at “L”)

96

TIR-WR

O

Data write strobe signal output to the external device    Not used (open)

97

TIR-CE0

O

Chip enable signal output to the external device    Not used (open)

98

TIR-CE1

O

Chip enable signal output to the external device    Not used (open)

99

TIR-RES

O

Reset signal output to the external device    “H”: reset    Not used (open)

100

TIR-PDOWN

O

Power down control signal output to the external device    “L”: power down    Not used (open)

101

TIR-RD

O

Data read strobe signal output to the external device    Not used (open)

102

MTLIN

I

Metal detection signal input terminal    “L”: normal position, “H”: metal position

103

AMSIN

I

Whether a music is present or not from CXA2510AQ (IC250) is detected at auto music sensor
“L”: music is present, “H”: music is not present

104

REEL

I

Rotation detect signal input from supply reel sensor and take-up reel sensor on the deck 
mechanism

105

POS0

I

106

POS1

I

107

POS2

I

108

POS3

I

109

LM-EJ

O

Motor drive signal output to the loading/tape operation motor drive (IC201)    “H” active
(For the eject direction and reverse side operation)    *1

Tape position (EJECT/FF/REW/
REV/FWD mode) detect input from 
the tape operation switch on the deck 
mechanism

POS0: “L”: EJECT mode, “H”: others mode
POS1: “L”: FF and FWD mode, “H”: others mode
POS2: “L”: REW mode, “H”: others mode
POS3: “L”: REV and EJECT mode, “H”: others mode