Circuit Description - Kenwood KRC-28YG Service Manual

(X14-) IC1 : SYSTEM u-COM
PORT
PORT NAME I/O
No.
1 XIN I
2 TEST 2 -
3 LCD DATA IN I
4 LCD DATA OUT O
5 LCD CLK O
6 STBY I
7 T END I
8 SDA 2 I/O Data line to E-VOL.
9 SCL 2 O
10 REQ H O
11 DATA C I
12 DATA H O
13 CH CLK I
14 REQ C I
15 CH CON O
16 LCD CE O
17 AM+B O
18 FM+B O
19 MUTE O
20 ILLUMI O
21 AMP STBY O
22 SVR O
23 P.CON O
24 ANT CONT O
25 SUB+ O
26 SUB- O
27 - -
28 SEL 2 I
29 SEL 1 I
30 SEL 0 I
31 VDD -
32 N.CAN I
33 MOTOR O
34-
- -
36
37 DSI O
38 EQ MUTE O
39 P.ON O
40 - -

CIRCUIT DESCRIPTION

FUNCTION
Clock input
GND
LCD driver data input
LCD driver data output
LCD driver clock output
Tape stand-by SW
Tape end SW
Clock line to E-VOL.
Changer request output
Changer data input
Changer data output
Changer clock input
Changer request input
Changer control
LCD driver Chip Enable output
AM power supply control
FM power supply control
Mute output for audio circuit
Illumination on
Stand-by output to power amp
SVR discharge circuit control
Power control
Tuner ANT control
Sub motor+output
Sub motor-output
-
Destination discrimination 2
Destination discrimination 1
Destination discrimination 0
VDD
Noise canceller setting
Motor-ON output
-
Disable System Indicator
Tape equaliser mute output
Power on
-
KRC-28YG/YA
(X14-) IC1 : SYSTEM u-COM
PORT
PORT NAME I/O
No.
41 - -
42 MS CONT O
43 - -
44 BEEP O
45 PANEL I
46 AMP MUTE O
47 CRSC I
48 PACK IN I
49 FWD/REV I
50 SDA3 O
51 SCL3 O
52 METAL O
53 DOLBY O
54 AM IF CONT I
55 SD I
56 REMOTE I
57-
- -
60
61 T MODE I
62 PHONE I
63 ACC I
64 BACK UP I
65 MUSIC I
66 S-METER I
67 HOLD I
68 SNS I
69 LCTR -
70 HCTR -
71,
- -
72
73 VDD -
74 AM IN -
75 FM IN -
76 VSS -
77,
- -
78
79 TEST1 -
80 XOUT I
FUNCTION
-
-
-
Beep output(2.08KHz)
Panel ON/OFF detection
Mute
-
Pack-in detection
Tape FWD/REV
PLL/EEPROM data line
PLL/EEPROM clock line
Metal mode ON/OFF
Dolby
AM IF count judgement
SD input
Remote controller
-
Mode pulse input
Telephone mute input
ACC detection
Back Up detection
Tape signal detection
FM band SD detection
Hold Detection
-
GND
GND
-
VDD
GND
GND
GND
-
GND
Clock output
3