Microcomputer's Terminal Description - Kenwood KDC-8024 Service Manual

Ref. No. Application/Function
Q26 Small lamp det SW
Q27 BU det
Q29 ACC det
Q30, 31 Mute driver
Q201 Noise buffer
Q202 E-vol mute SW
Q203~208 Pre-out mute SW
Q210 AGC for SA
Q303, 304 AM+B SW
Q305 Composite signal buffer for RDS
Q501 E2P 5V SW
Q502, 503 PANEL 5V SW
Q603 SW for IC20

MICROCOMPUTER'S TERMINAL DESCRIPTION

SYSTEM MICROCOMPUTER : 703033BGC021 (X25-964 : IC1)
Pin No. Pin Name I/O
1 PLL_DATA I/O
2 AM+B I/O
3 (FM+B) O
4 V_ILL PAN_E2P DATA I/O
5 V_ILL PAN_E2P CLK I/O
6 EVDD -
7 EVSS -
8 AFS O
9 BEEP O
10 REMO I
11 P_MUTE O
12 (SVR) O
13 IC2_SDA I/O
14 IC2_CLK I/O
15 P_STBY O
16 P_CON I/O
17 WOW_MODE2 O
18 TEST -
COMPONENTS DESCRIPTION
When Q26'base goes Hi, Q26 is turned on.
When Q27'base gose Hi, Q27 is turned on.
When Q29'base gose Hi, Q29 is turned on.
When a base gose Lo, mute driver is turned on.
When a base gose Hi, mute SW is turned on.
When a base gose Hi, Pre-out is muted.
When Q303'base gose Hi, AM+B is out.
When Q501'base gose Lo, E2P 5V is out.
When Q503'base gose Hi, PANEL 5V is out.
When Q603'base gose Hi, Q603 is turned on.
Module Purpose / Description
Tuner Data output/input with F/E.
Power supply AM+B.
Power supply FM+B (S01 F/E only).
To panel V-ILL D/A converter (V-ILL, LCD), E2PROM data.
To panel V-ILL D/A converter (V-ILL, LCD), E2PROM clock.
Tuner Noise detection time constant switching.
Audio Beep output.
Extra Remote control input (Panel, External display).
Audio Power IC MUTE output.
Audio Power IC SVR discharge circuit control.
CD CD mechanism data line.
Audio IC2, IC5 data line.
Extra ROM correction data line.
CD CD mechanism clock line.
Audio IC2, IC5 clock line.
Extra ROM correction clock line.
Audio Power IC STBY output.
Extra Power control.
Audio WOW control.
KDC-8024
Operation/Condition/Compatibility
Truth table Processing Operation
AM operation : H
FM operation : H,
Last FM : H (With RDS, RBDS model)
FM seek, AF search : L, Receiving : H, Auto 0 : L
Power OFF : L, All OFF : L, TEL mute : L
Power OFF momentary power dropped
: H (5 second) and then L
Power IC ON : H, Power IC OFF : L, All OFF : H
Power ON : H, Power OFF : Hi-Z, All OFF : Hi-Z
q
Connect to GND.
5