8-bit microcontrollers with accelerated two-clock 80C51 core
4 kB/8 kB 3 V low-power Flash with 8-bit A/D converter
Rev. 03 — 15 December 2004
1. General description
The P89LPC924/925 are single-chip microcontrollers designed for applications
demanding high-integration, low cost solutions over a wide range of performance
requirements. The P89LPC924/925 is based on a high performance processor
architecture that executes instructions in two to four clocks, six times the rate of
standard 80C51 devices. Many system-level functions have been incorporated into
the P89LPC924/925 in order to reduce component count, board space, and system
2.1 Principal features
s 4 kB/8 kB Flash code memory with 1 kB erasable sectors, 64-byte erasable page
size, and single byte erase.
s 256-byte RAM data memory.
s Two 16-bit counter/timers. Each timer may be conﬁgured to toggle a port output
upon timer overﬂow or to become a PWM output.
s Real-Time clock that can also be used as a system timer.
s 4-input 8-bit multiplexed A/D converter/single DAC output. Two analog
comparators with selectable inputs and reference source.
s Enhanced UART with fractional baud rate generator, break detect, framing error
detection, automatic address detection and versatile interrupt capabilities.
s 400 kHz byte-wide I2C-bus communication port.
s Conﬁgurable on-chip oscillator with frequency range and RC oscillator options
(selected by user programmed Flash conﬁguration bits). The RC oscillator (factory
calibrated to ±1 %) option allows operation without external oscillator
components. Oscillator options support frequencies from 20 kHz to the maximum
operating frequency of 18 MHz. The RC oscillator option is selectable and ﬁne
s 2.4 V to 3.6 V VDD operating range. I/O pins are 5 V tolerant (may be pulled up or
driven to 5.5 V).
s 15 I/O pins minimum. Up to 18 I/O pins while using on-chip oscillator and reset