4function Calculator four function calculator with four 7seg and 4x4 keyboard.It can handle numerical(2digit numbers) operations using + - * / (download .DSN file for Proteus) Samples: 99/0 12/99 32-45 99*99 (C) Copyright 1997 - 2008 by Vault Information Services LLC. All Rights Reserved. Information provided "as-is" without warranty. Please see details. Contact us for usage and copy permission.