while you will be able to get it by Google search, please use its younger brother 89S52 for cost and ISP flash programming ease. you get lot of programs for that purpose on 8052.com
can any1 help me how can i create a password recognisation system using AT89S51/AT89S2051 and a 3X4 Keyboard... in net i m getting the abstract but not being able to get the program or logic... please help, its urgent....