CPU & VHDL           Resources: 2

Books on Digital/CPU :

Computer Systems Organization & Architecture, John Carpinelli, Addison Wesley
excellent, I use it a lot for this module
but, there's only a little VHDL in it.

Digital Design, Principles & Practices, J. Wakerly, Prentice Hall
v. good digital cookbook with some Verilog &VHDL
Has just been republished; 4th Edition, 45 ukp
lots of them in the library :) but only 3rd Ed.

Computer Systems Design & Architecture, V. Heuring & H. Jordan, Addison Wesley
Could be good for Advanced CPU Architecture (lvl 3)
Again, use the library.