Big multiplexer?

Discussion in 'VHDL' started by bxbxb3, Apr 15, 2005.

  1. bxbxb3

    bxbxb3 Guest

    Hi,
    I have 64Kbytes of ROM and supposing all the 65536 locations of ROM are
    filled with opcodes, I have to read each locations one by one. This can be
    done through the use of a multiplexer with 64K*8 input lines, and a program
    counter.....or is there any other alternative other than designing such a
    massive multiplexer with 64K*8 input lines or is this the only way?
    Thanks in advance.
    bxbxb3, Apr 15, 2005
    #1
    1. Advertising

  2. bxbxb3 wrote:


    > I have 64Kbytes of ROM


    ROM or an constant array?

    > and supposing all the 65536 locations of ROM are
    > filled with opcodes, I have to read each locations one by one. This can be
    > done through the use of a multiplexer with 64K*8 input lines, and a program
    > counter.....or is there any other alternative other than designing such a
    > massive multiplexer with 64K*8 input lines or is this the only way?


    What is your target architecture? FPGA, ASIC? Does your target offer a ROM?


    Ralf
    Ralf Hildebrandt, Apr 15, 2005
    #2
    1. Advertising

  3. bxbxb3

    bxbxb3 Guest

    My target architecture is FPGA. It doesn't offer a ROM.
    bxbxb3, Apr 17, 2005
    #3
  4. bxbxb3 wrote:
    > Hi,
    > I have 64Kbytes of ROM and supposing all the 65536 locations of ROM are
    > filled with opcodes, I have to read each locations one by one. This can be
    > done through the use of a multiplexer with 64K*8 input lines, and a program
    > counter.....or is there any other alternative other than designing such a
    > massive multiplexer with 64K*8 input lines or is this the only way?


    If you already have the ROM,
    you already have the multiplexer.

    -- Mike Treseler
    Mike Treseler, Apr 17, 2005
    #4
  5. bxbxb3 wrote:

    > My target architecture is FPGA. It doesn't offer a ROM.


    Really? Many FPGAs offer Block-RAM, that can be initialized, which is
    the same as ROM.

    Ralf
    Ralf Hildebrandt, Apr 17, 2005
    #5
  6. bxbxb3

    bxbxb3 Guest

    Well, I wanted three multiplexers, one for reading opcode and the other two
    for operands!
    bxbxb3, Apr 19, 2005
    #6
    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. Shaguf
    Replies:
    0
    Views:
    325
    Shaguf
    Dec 24, 2008
  2. Shaguf
    Replies:
    0
    Views:
    430
    Shaguf
    Dec 26, 2008
  3. Massi
    Replies:
    6
    Views:
    1,728
  4. Shaguf
    Replies:
    0
    Views:
    217
    Shaguf
    Dec 26, 2008
  5. Shaguf
    Replies:
    0
    Views:
    199
    Shaguf
    Dec 24, 2008
Loading...

Share This Page