This is an 80C51 8-bit Flash microcontroller family, 16KB/32KB/64KB ISP/IAP Flash with 512B/512B/1KB RAM
The Philips P89C51RB2/P89C51RC2/P89C51RD2Hxx is a single-chip 8-bit microcontroller manufactured in an advanced CMOS process. It is a derivative of the 80C51 family and features a non-volatile Flash program memory ranging from 16KB to 64KB, which supports both In-System Programming (ISP) and In-Application Programming (IAP). The device includes a Boot ROM containing low-level Flash programming routines, allowing for serial programming via the UART without external loaders.
Key features include four 8-bit I/O ports, three 16-bit timer/event counters, an enhanced UART with automatic address recognition, and a multi-source, four-priority-level nested interrupt structure. The microcontroller operates at speeds up to 20 MHz (6 clocks per machine cycle) or 33 MHz (12 clocks per machine cycle) and supports various power control modes, including Stop Clock, Idle, and Power-Down modes.
| Program Memory | 16KB/32KB/64KB Flash |
|---|---|
| RAM | 512B/512B/1KB |
| Operating Temperature (0 to +70) | 0 to +70 °C |
| Operating Temperature (-40 to +85) | -40 to +85 °C |
| Max Frequency (6 clock mode) | 0 to 20 MHz |
| Max Frequency (12 clock mode) | 0 to 33 MHz |
| I/O Ports | Four 8-bit I/O ports |
| Timers | Three 16-bit timer/event counters |
| Interrupts | Seven interrupt sources |
| Interrupt Priority | Four interrupt priority levels |
| UART | Full-duplex enhanced UART |
In-System Programming (ISP) allows downloading new code while the microcontroller sits in the application, whereas In-Application Programming (IAP) means the microcontroller fetches new program code and reprograms itself while in the system.
Yes, the RAM is expandable externally to 64 kbytes.
The device executes one machine cycle in 6 clock cycles by default, but an OTP configuration bit allows the user to select conventional 12 clock timing.