This part is a kind of semiconductor called 89C51.

Function of this product has 8 Bit Microcontroller with 4 Kbytes Flash.

Manufacturers : atmel

Image and pinout :

Some of the text within the PDF file :

Features • • • • • • • • • • Compatible with MCS-51™ Products 4 Kbytes of In-System Reprogrammable Flash Memory Endurance: 1,000 Write/Erase Cycles Fully Static Operation: 0 Hz to 24 MHz Three-Level Program Memory Lock 128 x 8-Bit Internal RAM 32 Programmable I/O Lines Two 16-Bit Timer/Counters Six Interrupt Sources Programmable Serial Channel Low Power Idle and Power Down Modes Description The AT89C51 is a low-power, high-performance CMOS 8-bit microcomputer with 4 Kbytes of Flash Programmable and Erasable Read Only Memory (PEROM). The device is manufactured using Atmel’s high density nonvolatile memory technology and is compatible with the industry standard MCS-51™ instruction set and pinout. The on-chip Flash allows the program memory to be reprogrammed in-s [ ... ]

89C51 PDF Datasheet Download