DESCRIPTION
The P89C660/662/664/668 device contains a non-volatile 16KB/32KB/64KB Flash program memory that is both parallel programmable and serial In-System and In-Application Programmable. In-System Programming (ISP) allows the user to download new code while the microcontroller sits in the application.

FEATURES
• 80C51 Central Processing Unit
• On-chip Flash program memory with In-System Programming (ISP) and In-Application Programming (IAP) capability
• Boot ROM contains low level Flash programming routines for downloading via the UART
• Can be programmed by the end-user application (IAP)
• Parallel programming with 87C51 compatible hardware interface to programmer
• Six clocks per machine cycle operation (standard)
• 12 clocks per machine cycle operation (optional)
• Speed up to 20 MHz with 6 clock cycles per machine cycle (40 MHz equivalent performance); up to 33 MHz with 12 clocks per machine cycle
• Fully static operation
• RAM externally expandable to 64 kbytes
• Four interrupt priority levels
• Eight interrupt sources
• Four 8-bit I/O ports
• Full-duplex enhanced UART
    – Framing error detection
    – Automatic address recognition
• Power control modes
    – Clock can be stopped and resumed
    – Idle mode
    – Power-Down mode
• Programmable clock out
• Second DPTR register
• Asynchronous port reset
• Low EMI (inhibit ALE)
• I2C serial interface
• Programmable Counter Array (PCA)
    – PWM
    – Capture/compare
• Well-suited for IPMI applications