Don't care signals

Discussion in 'VHDL' started by bittor, Feb 14, 2005.

  1. bittor

    bittor Guest

    Hello,
    I want to do something like if ( signal_A=signal_B) then...
    Where I want to have one of the signals with don't care. Then always
    signal_A=signal_B. I tried to do this with types (X,U,-,etc...) but it
    doesn't work.
    Anyone can help me?
    Thanks
     
    bittor, Feb 14, 2005
    #1
    1. Advertising

  2. bittor wrote:

    > Hello,
    > I want to do something like if ( signal_A=signal_B) then...
    > Where I want to have one of the signals with don't care. Then always
    > signal_A=signal_B. I tried to do this with types (X,U,-,etc...) but it
    > doesn't work.
    > Anyone can help me?


    Comp.lang.vhdl FAQ, Part 1, section 4.2.9 "Don’t Cares" in VHDL

    http://www.eda.org/comp.lang.vhdl/
    --
    Tim Hubberstey, P.Eng. . . . . . Hardware/Software Consulting Engineer
    Marmot Engineering . . . . . . . VHDL, ASICs, FPGAs, embedded systems
    Vancouver, BC, Canada . . . . . . . . . . . http://www.marmot-eng.com
     
    Tim Hubberstey, Feb 14, 2005
    #2
    1. Advertising

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. Gregory Huffman

    How to include don't care minterms

    Gregory Huffman, Jan 26, 2004, in forum: VHDL
    Replies:
    3
    Views:
    7,587
    Gregory Huffman
    Jan 28, 2004
  2. Andrew Greensted

    Don't care and optimization

    Andrew Greensted, Jan 10, 2006, in forum: VHDL
    Replies:
    3
    Views:
    3,225
    Andrew Greensted
    Jan 11, 2006
  3. Simon  Willison
    Replies:
    8
    Views:
    307
    John J. Lee
    Oct 3, 2006
  4. M. Norton

    Use of std_logic '-' don't care.

    M. Norton, Oct 17, 2008, in forum: VHDL
    Replies:
    5
    Views:
    952
    M. Norton
    Oct 20, 2008
  5. janeruth

    conditional on a don't care

    janeruth, Aug 3, 2010, in forum: VHDL
    Replies:
    4
    Views:
    739
    janeruth
    Aug 4, 2010
Loading...

Share This Page