AT89 ATMEL Corporation, AT89 Datasheet - Page 2

• Manufacturer Part Number: AT89
• Description: 8-Bit Microcontroller with 4K Bytes Flash
• Manufacturer: ATMEL Corporation

Block Diagram
ALE/PROG
4-30
EA / V
PSEN
RST
V
GND
PP
CC
CONTROL
REGISTER
TIMING
AND
OSC
B
RAM ADDR.
REGISTER
AT89C51
INSTRUCTION
REGISTER
ACC
TMP2
RAM
PORT 1 DRIVERS
PSW
P1.0 - P1.7
PORT 0 DRIVERS
PORT 1
LATCH
ALU
P0.0 - P0.7
PORT 0
LATCH
TMP1
INTERRUPT, SERIAL PORT,
AND TIMER BLOCKS
PORT 2
LATCH
PORT 3 DRIVERS
PORT 2 DRIVERS
POINTER
STACK
P2.0 - P2.7
P3.0 - P3.7
PORT 3
LATCH
FLASH
INCREMENTER
PROGRAM
REGISTER
PROGRAM
COUNTER
ADDRESS
BUFFER
DPTR
PC