GENERAL DESCRIPTION

The DS89C420 offers the highest performance available in 8051-compatible microcontrollers. It features a redesigned processor core that executes every 8051 instruction (depending on the instruction type) up to 12 times faster than the original for the same crystal speed. Typical applications see a speed improvement of 10 times using the same code and crystal. The DS89C420 offers a maximum crystal speed of 33MHz, achieving execution rates up to 33 million instructions per second (MIPS).

FEATURES

■ 80C52 Compatible

    8051 Pin- and Instruction-Set Compatible

    Four Bidirectional I/O Ports

    Three 16-Bit Timer Counters

    256 Bytes Scratchpad RAM

■ On-Chip Memory

    16kB Flash Memory

    In-System Programmable through Serial Port

    1kB SRAM for MOVX

■ ROMSIZE Feature

    Selects Internal Program Memory Size from

        0 to 16k

    Allows Access to Entire External Memory Map

    Dynamically Adjustable by Software

■ High-Speed Architecture

    1 Clock-Per-Machine Cycle

    DC to 33MHz Operation

    Single-Cycle Instruction in 30ns

    Optional Variable Length MOVX to Access

        Fast/Slow Peripherals

    Dual Data Pointers with Auto

        Increment/Decrement and Toggle Select

    Supports Four Paged Modes

■ Power Management Mode

    Programmable Clock Divider

    Automatic Hardware and Software Exit

■ Two Full-Duplex Serial Ports

■ Programmable Watchdog Timer

■ 13 Interrupt Sources (Six External)

■ Five Levels of Interrupt Priority

■ Power-Fail Reset

■ Early Warning Power-Fail Interrupt

APPLICATIONS

    Data Logging

    Vending

    Automotive Test Equipment

    Motor Control

    Magstripe Reader/Scanner

    Consumer Electronics

    Gaming Equipment

    Appliances (Washers, Microwaves, etc.)

    Telephones

    HVAC

    Building Security and Door Access Control

    Building Energy Control and Management

    Uninterruptible Power Supplies

    Programmable Logic Controllers

    Industrial Control and Automation