Intel 8253 - Block Diagram

Philips Semiconductors Product specification
80C31/80C32
80C51 8-bit microcontroller family
128/256 byte RAM ROMless low voltage (2.7V–5.5V),
low power, high speed (33 MHz)
2000 Aug 07
4
BLOCK DIAGRAM
SU00845
PSEN
EAV
PP
ALE/PROG
RST
XTAL1 XTAL2
V
CC
V
SS
PORT 0
DRIVERS
PORT 2
DRIVERS
RAM ADDR
REGISTER
RAM
PORT 0
LATCH
PORT 2
LATCH
ROM/EPROM
REGISTER
B
ACC
STACK
POINTER
TMP2
TMP1
ALU
TIMING
AND
CONTROL
INSTRUCTION
REGISTER
PD
OSCILLATOR
PSW
PORT 1
LATCH
PORT 3
LATCH
PORT 1
DRIVERS
PORT 3
DRIVERS
PROGRAM
ADDRESS
REGISTER
BUFFER
PC
INCRE-
MENTER
PROGRAM
COUNTER
DPTR’S
MULTIPLE
P1.0–P1.7
P3.0–P3.7
P0.0–P0.7 P2.0–P2.7
SFRs
TIMERS
8
8 16