Panasonic SA-HT280 Service Manual page 22

11. Block Diagram
12. Wiring Connection Diagram
13. Terminal Functions of ICs
13.1. IC901 (M38B57M6141F) System Microprocessor
Pin / Mark
No. Division
1-2 KEY2-KEY1
3 THERM/
OVLD
4 KEY4
5
OVERLOAD2
6 FMST
7 WAKW
8 RDS DI
9 REMOTE
10 RESET
11 RDS CK
12 RDS DT
13 GND
14 XIN
15 XOUT
16 VDD (+5V)
17 LED CK
18 LED DATA
19 SFC1
20 SFC2
I/O / Function
I Key input 1-2
I Thermal/Over load input
I Key input 4
I Over load input 2
I Stereo signal detect
terminal
- Wake up timer LED /
(Not used, open)
- Control of RDS IC / (Not
used, open)
I Remote control terminal
I Reset detect terminal
- Control of RDS IC (CK)
clock / signal (Not used,
open)
- Control of RDS IC (DT)
data signal / (Not used,
open)
- GND terminal
I Crystal oscillator
terminal (4 MHz)
O Crystal oscillator
terminal (4 MHz)
- Power supply terminal +
5V
O LED driver IC (CK) clock
signal
O LED driver IC (DT) data
signal
I SFC mode encoder input
1
I SFC mode encoder input
2