Block Diagram - NAD C 325BEE Service Manual

AT89C4051
KEY BOARD IC73
Pin Configuration
PDIP/SOIC
Vcc
GND
RST/VPP 1 20
VCC
(RXD) P3.0 2 19
P1.7
(TXD) P3.1 3 18
P1.6
XTAL2 4 17
P1.5
XTAL1 5 16
P1.4
( INT0 ) P3.2 6 15
P1.3
( INT1 ) P3.3 7 14
P1.2
(TO) P3.4 8 13 P1.1 (AIN1)
(T1) P3.5 9 12 P1.0 (AIN0)
GND 10 11
P3.7
RST

Block Diagram

RAM ADDR.
RMA
REGISTER
B
ACC
REGISTER
TMP2
PSW
TIMING
INSTRUCTION
AND
REGISTER
CONTROL
ANALOG
COMPARATOR
+
-
OSC
PORT 1 DRIVERS
P 1.0 - P 1.7
14
FLASH
STACK
POINTER
TMP1
ALU
INTERRUPT SERIAL PORT
AND TIMER BLOCKS
PORT 1
PORT 3
LATCH LATCH
PORT 3 DRIVERS
P 3.0 - P 3.5
PROGRAM
ADDRESS
REGISTER
BUFFER
PC
INCREMENTER
PROGRAM
COUNTER
DPTR
P 3.7
www.hifiengine.com