hello asif….
you can use any of the language to make the code logic at the end you need to convert that code into hex file.. here the link i had given above has code in C language… use keil compiler to convert the C code to hex code here i an sending you the link how to convert you C code to hex code
http://www.engineersgarage.com/forums/8051/how-convert-c-code-hex-code-using-keil-compiler