include floating point library in vhdl

I have pex_pkg.vhd and I want to use this library to make floating point adder but altera max+plus II give me an error can't open "PEX_lib" how to include this library in max+plu开发者_如何学编程s ?

I'd stay away from Max plus II if I were you, it's v. old - its VHDL support was always spotty, and IIRC using libraries other than work wasn't possible.

Altera's tool is Quartus now - I'm sure that can handle multiple libraries.

You should check out David Bishop's VHDL Floating Point Library. This is by the same author who wrote the VHDL floating point libraries that are build into VHDL 2008, but these are usable with older and more common VHDL tools. They are fully tested and synthesizable. The only potential downside is that because they are implemented via functions, they can only describe the common case of either pipelined or combinational data paths. (If you want, for instance, a smaller multi-cycle digit-serial design, you have to resort to a different library.)

Are you sure you wish that? Most floating point libraries aren't synthesizable.