GENERAL DESCRIPTION
The W78IE54 is an 8-bit microcontroller which can accommodate a wide supply voltage range with low power consumption. The W78IE54 can operate normally within the temperature of industrial standard range from –40 to 85°C. The instruction set for the W78IE54 is fully compatible with the standard 8051. The W78IE54 contains an 16K bytes MTP ROM (Multiple-Time Programmable ROM); a 256 bytes RAM; four 8-bit bi-directional and bit-addressable I/O ports; an additional 4-bit I/O port P4; three 16-bit timer/counters; a hardware watchdog timer and a serial port. These peripherals are supported by eight sources two-level interrupt capability.

FEATURES
• Fully static design 8-bit CMOS microcontroller
• Wide supply voltage of 2.4V to 5.5V
• Wide operating temperature range from -40 °C to 85 °
• DC-40 MHz operation
• 256 bytes of on-chip scratchpad RAM
• 16 KB electrically erasable/programmable MTP-ROM
• 64 KB program memory address space
• 64 KB data memory address space
• Four 8-bit bi-directional ports
• One extra 4-bit bit-addressable I/O port, additional INT2 / INT3 (available on 44-pin PLCC package)
• Three 16-bit timer/counters
• One full duplex serial port(UART)
• Watchdog Timer
• Eight sources, two-level interrupt capability
• EMI reduction mode
• Built-in power management
• Code protection mechanism
• Packages:
    - DIP 40: W78IE54
    - PLCC 44: W78IE54P