DESCRIPTION

The 89C51RB2/RC2/RD2 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. In-Application Programming (IAP) means that the microcontroller fetches new program code and reprograms itself while in the system. This allows for remote programming over a modem link. A default serial loader (boot loader) program in ROM allows serial In-System programming of the Flash memory via the UART without the need for a loader in the Flash code. For In-Application Programming, the user program erases and reprograms the Flash memory by use of standard routines contained in ROM. This device executes one machine cycle in 6 clock cycles, hence providing twice the speed of a conventional 80C51. An OTP configuration bit lets the user select conventional 12 clock timing if desired.

This device is a Single-Chip 8-Bit Microcontroller manufactured in advanced CMOS process and is a derivative of the 80C51 microcontroller family. The instruction set is 100 compatible with the 80C51 instruction set.

The device also has four 8-bit I/O ports, three 16-bit timer/event counters, a multi-source, four-priority-level, nested interrupt structure, an enhanced UART and on-chip oscillator and timing circuits.

The added features of the P89C51RB2/RC2/RD2 makes it a powerful microcontroller for applications that require pulse width modulation, high-speed I/O and up/down counting capabilities such as motor control.

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)

? 6 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 expandable externally to 64 kB

? 4 level priority interrupt

? 8 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)

? Programmable Counter Array (PCA)

– PWM

– Capture/compare