This part is a kind of semiconductor called MC9S12DG256.

Function of this product has MC9S12DT256 Device User Guide V03.03.

Manufacturers : Motorola

Image and pinout :

Some of the text within the PDF file :

DOCUMENT NUMBER 9S12DT256DGV3/D MC9S12DT256 Device User Guide V03.03 Covers also MC9S12A256, MC9S12DJ256 MC9S12DG256, Original Release Date: 24 March 2003 Revised:26 July 2003 Motorola, Inc Motorola reserves the right to make changes without further notice to any products herein to improve reliability, function or design. Motorola does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Motorola pro [ ... ]

MC9S12DG256 PDF Datasheet Download