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