This part is a kind of semiconductor called 80C31X2.

Function of this product has 80C51 8-bit microcontroller family 4K/8K/16K/32K ROM/OTP 128B/256B RAM low voltage 2.7 to 5.5 V/ low power/ high speed 30/33 MHz.

Manufacturers : NXP

Image and pinout :

Some of the text within the PDF file :

INTEGRATED CIRCUITS 80C31X2/32X2 80C51X2/52X2/54X2/58X2 87C51X2/52X2/54X2/58X2 80C51 8-bit microcontroller family 4K/8K/16K/32K ROM/OTP 128B/256B RAM low voltage (2.7 to 5.5 V), low power, high speed (30/33 MHz) Preliminary data 2001 Sep 24 Philips Semiconductors Philips Semiconductors Preliminary data 80C51 8-bit microcontroller family 4K/8K/16K/32K ROM/OTP, low voltage (2.7 to 5.5 V), low power, high speed (30/33 MHz) 80C3xX2; 80C5xX2; 87C5xX2 DESCRIPTION The Philips microcontrollers described in this data sheet are high-performance static 80C51 designs incorporating Philips’ high-density CMOS technology with operation from 2.7 V to 5.5 V. They support both 6-clock and 12-clock operation. The 8xC31X2/51X2 and 8xC32X2/52X2/54X2/58X2 contain 128 byte RAM and 256 byte RAM respectiv [ ... ]

80C31X2 PDF Datasheet Download