Datasheet

2
A/T89C51AC2
4127H–8051–02/08
Block Diagram
Notes: 1. 8 analog Inputs/8 Digital I/O
2. 2-Bit I/O Port
Timer 0
INT
RAM
256x8
T0 T1
RxD TxD
WR
RD
EA
PSEN
ALE
XTAL2
XTAL1
UART
CPU
Timer 1
INT1
Ctrl
INT0
C51
CORE
Port 0
P0
Port 1
Port 2
Port 3
Parallel I/O Ports and Ext. Bus
P1(1)
P2 P3
XRAM
1kx8
IB-bus
PCA
RESET
Watch
Dog
PCA ECI
Vss Vcc
Timer 2
T2EX
T2
Port 4
P4(2)
10 bit
ADC
Flash
32kx
8
Boot
loader
2kx8
EE
PROM
2kx8
VAREF VAVCC VAGND