Datasheet

3
AT89C51IC2
4301D–8051–02/08
Block Diagram
Figure 1. Block Diagram
(1): Alternate function of Port 1
(2): Alternate function of Port 3
Timer 0
INT
RAM
256
T0 T1
RxD TxD
XTAL2
XTAL1
EUART
CPU
Timer 1
INT1
Ctrl
INT0
C51
CORE
(2) (2) (2) (2)
Port 0
Port 1
P1
P4
IB-bus
Reset
Vss Vcc
(2)(2)
Flash
32K x 8
x8
ECI PCA
(1)(1)
Port 2
P3
PCA Timer 2
BRG
Port 3
Port 12
P0
P2
EA
RD
WR
ALE/PROG
PSEN
(2)
(2)
+
Parallel I/O Ports & Ext Bus
Watch
Dog
Key
Board
SPI
SS
(1)
SCK
(1)
MOSI
(1)
MISO
(1)
T2EX
(1)
T2
(1)
Two-Wire
SDA SCL