P51XAG30KBBD

CMOS single-chip 16-bit microcontroller

20-bit address range, 1 megabyte each program and data space.
2.7V to 5.5V operation (EPROM and OTP are 5V ± 5%)
32K bytes on-chip EPROM/ROM program memory
512 bytes of on-chip data RAM
Three counter/timers with enhanced features (equivalent to 80C51 T0, T1, and T2)
Watchdog timer
Two enhanced UARTs
Four 8-bit I/O ports with 4 programmable output configurations

data sheet: P51XAG30.pdf