Dear Mr.Joshi,

The output of IBMPC keyboard is availabale using only two I/O o=pins of 8051. The connector of keyboard has CLOCK and DATA pins, and it out puts the code of key pressed on these 2 lines, so you don't need to use 8255.
I have used it, and you can find the o/p timing and sequence of IBM-PC keyboard on internet.
You may check
www.pcguides.com

Regards

IJAZ