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ST7291L

1 GENERAL DESCRIPTION

1.1 INTRODUCTION

The ST7291L CMOS Microcontroller Unit is a

member of the ST7 family of microcontrollers. The

device is based on an industry-standard 8-bit core

and features an enhanced instruction set. Oscilla-

tor frequency may be as high as 8MHz, however,

thanks to the fully static design, operation is possi-

ble down to DC. Under software control, the

ST7291L may be placed in either WAIT or HALT

modes, thus reducing power consumption.

The enhanced instruction set and addressing

modes afford real programming potential. In addi-

tion to standard 8-bit data management, the

ST7291L features bit manipulation, 8x8 unsigned

multiplication and indirect addressing modes.

The device includes a CPU, ROM, RAM, I/O, an

on-chip oscillator, a timer with output compare

system and, depending on the version, a Low Volt-

age Detection (LVD) and Carrier Frequency gen-

eration for remote control applications.

Figure 2. ST7291L Block Diagram

OSCILLATOR

PORT A

PORT B

CARRIER FREQ.

8 BIT CORE

PA0..PA7 (8-bit)

PB0..PB7 (8-bit)

PC0, PC1, PC6, PC7

PORT C

LOW VOLTAGE

DETECTOR

TIMER

SYSTEM

PC5

CONTRO L

Internal

CLOCK

ROM

8K/12K/16K/24K/32K

RAM

256/384

GENERATOR

OSCout

OSCin

WKP

RESET