This part is a kind of semiconductor called 89C51.

Function of this product has 80C51 8-bit microcontroller family 4K/8K/16K/32K Flash.

Manufacturers : NXP

Image and pinout :

Some of the text within the PDF file :

INTEGRATED CIRCUITS 89C51/89C52/89C54/89C58 80C51 8-bit microcontroller family 4K/8K/16K/32K Flash Product specification 1999 Oct 27 Replaces Datasheets 89C51 of 1999 Apr 01 and 89C52/89C54/89C58 of 1999 Apr 01 Philips Semiconductors Philips Semiconductors Product specification 80C51 8-bit microcontroller family 4K/8K/16K/32K Flash 89C51/89C52/89C54/89C58 DESCRIPTION The 89C51/89C52/89C54/89C58 contain a non-volatile FLASH program memory that is parallel programmable. For devices that are serial programmable (In System Programmable (ISP) with a boot loader), see the 89C51RC+/89C51RD+ datasheet. Both families are Single-Chip 8-bit Microcontrollers manufactured in advanced CMOS process and are derivatives of the 80C51 microcontroller family. All the devices have the same instruction s [ ... ]

89C51 PDF Datasheet Download