CMOS single-chip 8-bit microcontrollers

The P80C652/83C652 Single-Chip 8-Bit Microcontroller is manufactured in an advanced CMOS process and is a derivative of the 80C51 microcontroller family. The 80C652/83C652 has the same instruction set as the 80C51. Three versions of the derivative exist:

83C652 - 8k bytes mask programmable ROM

80C652 - ROMless version

87C652 - EPROM version (described in a separate chapter)

This device provides architectural enhancements that make it applicable in a variety of applications for general control systems. The 8XC652 contains a non-volatile 8k ? 8 read-only program memory, a volatile 256 ? 8 read/write data memory, four 8-bit I/O ports, two 16-bit timer/event counters (identical to the timers of the 80C51), a multi-source, two-priority-level, nested interrupt structure, an I²C interface, UART and on-chip oscillator and timing circuits. For systems that require extra capability, the 8XC652 can be expanded using standard TTL compatible memories and logic.

The device also functions as an arithmetic processor having facilities for both binary and BCD arithmetic plus bit-handling capabilities. The instruction set consists of over 100 instructions: 49 one-byte, 45 two-byte and 17 three-byte. With a 16(24)MHz crystal, 58% of the instructions are executed in 0.75(0.5)µs and 40% in 1.5(1)µs. Multiply and divide instructions require 3(2)µs.