Kenwood KDC-8021, Service Manual

Page: 10 / 27

KDC-8021/M9021/X859
10
MICROCOMPUTER'S TERMINAL DESCRIPTION
Pin Name I/O Purpose Processing Operation
Processing During Processing During
Non-Operation STBY
74 Avdd -
Positive power supply
terminal.
75 Avss - GND terminal.
76 Avref I
A/D converter reference
voltage supply terminal.
77 PHONE I Phone detection terminal.
TEL muting: 1 V or less.
NAVI muting: 2.5 V or more.
78 E2PROMDET I
E2PROM detection E2PROM present: "H".
terminal. E2PROM absent: "L".
Mask mechanism
Refer to the 01MASK
79 MASK-SW1 I
position detection.
mechanism position
detection chart
Mask mechanism
Refer to the 01MASK
80 MASK-SW2 I
position detection.
mechanism position
detection chart
Mask mechanism
Refer to the 01MASK
81 MASK-SW3 I
position detection.
mechanism position
detection chart
82 MASK-DET I
Mask mechanism Mechanism present: "L".
detection. Mechanism absent: "H".
83 NOISE I
FM noise detection
terminal.
84 S-METER I
S-meter detection
terminal.
85 R-DATA I
RDS decoder DATA Models without RDS and
input terminal. RBDS: Connected to GND.
86 R-QUAL I
RDS decoder OUAL Models without RDS and
input terminal. RBDS: Connected to GND.
87 IFC-OUT I
F/E IFC OUT input Station detected: 2.5 V
terminal. or more.
88 CH-MUTE I Muting request from CH.
89 CH-REQH O Request output to CH. Request: "L". H H
90 R-CLK I
RDS decoder CLK input Models without RDS and
terminal. RBDS: Connected to GND.
91 CH-REQC I Request input from CH. Requested: "L".
92 SC-REQ I
Communication request
from Panel uCOM.
Loading start: "L".
93 CD-SW1 I
Loading SW detection Take care that the logic
terminal. in power OFF is different
from Flip.
12 cm disc detection
12 cm disc: "L". Take care
94 CD-SW2 I
SW terminal.
that the logic in power
OFF is different from Flip.
95 N.C O Output Open. Not used. L
96 N.C O Output Open. Not used. L
97 CH-DATAC I
DATA input terminal
from CH.
98 CH-DATAH O
DATA output terminal
to CH.
Last state held. L
99 CH-CLK I/O
CLK input/terminal
from/to CH.
Hi-Z
100 SC-DATA I
DATA line from
Panel uCOM.
Hi-Z
SYSTEM MICROCOMPUTER uPD703033AGF- *** -3BA (X25)