DESCRIPTION
The Philips 8XC453 is an I/O expanded single-chip microcontroller fabricated with Philips high-density CMOS technology. Philips epitaxial substrate minimizes latch-up sensitivity.
The 8XC453 is a functional extension of the 87C51 microcontroller with three additional I/O ports and four I/O control lines. The 8XC453 is available in 68-pin LCC packages. Four control lines associated with port 6 facilitate high-speed asynchronous I/O functions.
The 87C453 includes an 8k × 8 EPROM, a 256 × 8 RAM, 56 I/O lines, two 16-bit timer/counters, a seven source, two priority level, nested interrupt structure, a serial I/O port for either a full duplex UART, I/O expansion, or multi-processor communications, and on-chip oscillator and clock circuits.

FEATURES
• 80C51 based architecture
• Seven 8-bit I/O ports
• Port 6 features:
    – Eight data pins
    – Four control pins
    – Direct MPU bus interface
    – ISA Bus Interface
    – Parallel printer interface
    – IBF and OBF interrupts
    – A flag latch on host write
• On the microcontroller:
    – 8k × 8 EPROM
        Quick pulse programming algorithm
        Two-level program security system
    – 256 × 8 RAM
    – Two 16-bit counter/timers
    – Two external interrupts
• External memory addressing capability
    – 64k ROM and 64k RAM
• Low power consumption:
    – Normal operation: less than 24mA at 5V, 16MHz
    – Idle mode
    – Power-down mode
• Reduced EMI
• Full-duplex enhanced UART
    – Framing error detection
    – Automatic address recognition