GENERAL DESCRIPTION
The P89C738 and P89C739 (hereafter generally referred to as P89C738 unless the P89C739 is specifically mentioned) are 8 8-bit Flash microcontrollers manufactured in an advanced CMOS process and is a derivative of the PCB80C51 microcontroller family. This device provides architectural enhancements that make it applicable in a variety of applications in general control systems, especially in those systems which need a large on-chip ROM and RAM capacity.

FEATURES
• 80C51 CPU
• 64-kbyte on-chip Multiple Programming ROM (MTP-ROM), expandable externally to 64 kbytes program memory address space
• 512-byte on-chip RAM, expandable externally to 64 kbytes data memory address space
• P89C738 pin outs fully compatible to the standard 8051/8052
• 8-bit I/O ports for P89C738: 4 and P89C739: 6
• Full-duplex UART compatible with the standard 80C51 and the 8052
• Two standard 16-bit timers/event counters
• An additional 16-bit timer (functionally equivalent to the Timer 2 of the 8052)
• On-chip Watchdog Timer (T3)
• 6-source and 6-vector interrupt structure with 2 priority levels
• Up to 3 external interrupt request inputs
• Two programmable power reduction modes: Idle and Power-down
• Termination of Idle mode by any interrupt, external or Watchdog Timer reset
• Wake-up from Power-down by external interrupt, external or Watchdog Timer reset
• Packages, – P89C738: DIP40, PLCC44 and QFP44 – P89C739: PLCC68 and QFP64
• Improved Electromagnetic Compatibility (EMC)
• Frequency range: 3.5 to 40 MHz
• ROM code protection