80C851 Datasheet, PDF (3/22 Pages) NXP Semiconductors – CMOS single-chip 8-bit microcontroller with on-chip EEPROM

Philips Semiconductors
CMOS single-chip 8-bit microcontroller
with on-chip EEPROM
BLOCK DIAGRAM
FREQUENCY
REFERENCE
XTAL2 XTAL1
OSCILLATOR
AND
TIMING
PROGRAM
MEMORY
(4K x 8 ROM)
DATA
MEMORY
(128 x 8 RAM)
Product specification
80C851/83C851
COUNTERS
T0
T1
TWO 16-BIT
TIMER/EVENT
COUNTERS
EEPROM
(256 x 8)
CPU
INTERNAL
INTERRUPTS
64K BYTE BUS
EXPANSION
CONTRTOL
PROGRAMMABLE I/O
PROG SERIAL PORT
FULL DUPLEX UART
SYNCHRONOUS SHIFT
INT0 INT1
EXTERNAL
INTERRUPTS
LOGIC SYMBOL
CONTROL
V_DD
XTAL1
V_SS
XTAL2
RxD
TxD
INT0
INT1
T0
T1
WR
RD
RST
EA
PSEN
ALE
PARALLEL PORTS,
ADDRESS/DATA BUS
AND I/O PINS
SERIAL IN SERIAL OUT
SHARED WITH
PORT 3
ADDRESS AND
DATA BUS
ADDRESS BUS
1998 Jul 03
3