Описание
The P89C51RD2 nxp contains a non-volatile 8KB/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. The device supports 6-clock/12-clock mode selection by programming a Flash bit using parallel programming or In-System Programming. In addition, an SFR bit (X2) in the clock control register (CKCON) also selects between 6-clock/12-clock mode. Additionally, when in 6-clock mode, peripherals may use either 6 clocks per machine cycle or 12 clocks per machine cycle. This choice is available individually for each peripheral and is selected by bits in the CKCON register. This device is a Single-Chip 8-Bit Microcontroller manufactured in an 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 P89C51RD2 nxp make it a powerful microcontroller for applications that require pulse width modulation, high-speed I/O and up/down counting capabilities such as motor control.
- 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
- Supports 6-clock/12-clock mode via parallel programmer (default clock mode after ChipErase is 12-clock)
- 6-clock/12-clock mode Flash bit erasable and programmable via ISP
- 6-clock/12-clock mode programmable “on-the-fly” by SFR bit
- Peripherals (PCA, timers, UART) may use either 6-clock or 12-clock mode while the CPU is in 6-clock mode
- 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 kbytes
- Four interrupt priority levels
- Seven 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 pin
- Second DPTR register
- Asynchronous port reset
- Low EMI (inhibit ALE)
- Programmable Counter Array (PCA)
- PWM
- Capture/compare
