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Altera_Forum's avatar
Altera_Forum
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15 years ago

How to Design a Multiplier Circuit using AHDL?

Hi all:

I have a multiplier circuit built using Multisim and I suppoosed to use AHDL to implement the circuit. Problem is, I don't know where to begin and how to actually use the circuit. Here are the design parameters and the algorithms that I have.

Please the attached file. This is where I am getting stuck at. How do I actually write this into code?

Lew

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Step 1: Go to your tutor and tell him that AHDL is an old and unsupported language. From Quarus 10 you wont be able to simulate it at all.

    Step 2: Do it in a more modern HDL like VHDL or Verilog that are IEEE standard, not proprietry, languages.

    Otherwise: 

    
MultiplierA :    lpm_mult    WITH (    LPM_WIDTHA                                = 2 , 
                                            LPM_WIDTHB                                 = 2 ,
                                            LPM_WIDTHP                                 = 4 ,
                                            LPM_WIDTHS                                 = 1 ,
                                            LPM_REPRESENTATION                         = "UNSIGNED" ,
                                            LPM_PIPELINE                             = 1 ,
                                            INPUT_A_IS_CONSTANT                     = "NO" ,
                                            INPUT_B_IS_CONSTANT                     = "NO" ,
                                            USE_EAB                                     = "OFF"  ,
                                            DEDICATED_MULTIPLIER_CIRCUITRY             = "YES"
                                        ) ;
MultiplierA.clock = clk;
MultiplierA.clken = VCC;
MultiplierA.dataa = input1;
MultiplierA.datab = input2;
output = MultiplierA.result;
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Understable Tricky,

    However, these projects are for Digital Systems class and I think the purpose here is to get the understanding of PLD's and Programming down-packed. Not to actually use in a system. Can you explain what the device family is supposed to mean and how do you know which family and device to use with a particular circuit?

    LEW
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    The device family is the chip you chose. And which chip you chose really depends on application.

    If you want millions of gates and high-speed coms, you got for a stratix 4 ($thousands), if you need something cheap that can still do plenty you go for a cyclone 3 ($hundreds).

    With modern devices as they all have plenty of memory and embedded multipliers, there are only 2 main deciding factors

    1. Cost

    2. Comms required

    I get the feeling the question is aimed at much more outdated technology though.