XR-1300R, XR-C2300R - Sony Car Audio Service Manual (repair manual). Page 27

27

Pin No.

Pin Name

I/O

Description

77

BU-IN

I

Battery detect signal input from the SONY bus interface (IC800) and battery detect circuit
“L” is input at low voltage    IC800: Used for the XR-C2300R only

78

ILL IN

O

Not used

79

TELATT

I

Telephone muting signal input terminal    At input of “H”, the signal is attenuated by –20 dB
Not used

80

LCDCE

I

Chip enable signal output to the liquid crystal display driver (IC900)    “H” active

81

ACC IN

I

Accessory detect signal input terminal    “L”: accessory on

82 to 85

NC

O

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, 89

MD1, MD0

I

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

90

RSTX

I

System reset signal input from the reset signal generator (IC2) and reset switch (S2)
“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 to 104

NC

O

Not used (open)

105

TAPE IN

I

Tape in detection switch (S903) input terminal    “L”: tape in

106

FF-REW IN

I

FF/REW detection switch (S902) input terminal    “L”: FF/REW mode

107

N/R

I

Tape direction switch (S903) input terminal    “L”: reverse direction    “H”: forward direction

108 to 110

NC

O

Not used (open)

111

CM ON

O

Capstan/reel motor (M901) drive signal output terminal    “H”: motor on

112 to 116

NC

O

Not used (open)

117

TAPMUTE

O

Tape muting on/off control signal output terminal    “H”: muting on
Active at ATA, FF/REW mode    Not used (open)

118

AMPON

O

Standby on/off control signal output to the power amplifier (IC500)
“L”: standby mode, “H”: amp on

119

VSS

—

Ground terminal

120

PWON

O

Main system power supply on/off control signal output terminal    “H”: power on