P89LPC920/921/922 is an 80C51 8-bit microcontroller with two-clock core, 2KB/4KB/8KB 3V low-power Flash and 256 Byte RAM, launched by Philips Semiconductors
The Philips P89LPC920/921/922 is an 80C51‑compatible 8‑bit microcontroller featuring a two‑cycle core, low‑power operation at 3 V, and on‑chip flash memory options of 2 KB, 4 KB or 8 KB. It includes 256 Byte of data RAM, a range of peripheral interfaces (UART, I²C, timers, comparators, watchdog, and real‑time clock) and extensive power‑management functions.
The manual provides detailed descriptions of the pin configuration, clock options, interrupt architecture, I/O port modes, and programming resources such as in‑system programming (ISP) and flash memory usage. It also covers special features like keypad interrupt, watchdog timer, and flash security bytes, making it a comprehensive reference for designers and developers.