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Altera_Forum's avatar
Altera_Forum
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14 years ago

Filter on DE2 board HELP!

As part of a porject, i'm expected to do this design a simple low-pass filter, using the Fdesign tool in matlab. then generate a VHDL file and test bench to simulate in modelsim/Quartus.

The final step is to test the low-pass filter on the DE2 board.

The first 2 steps are done. the final step is the problem. i don't know how to test this on the DE2 board. how do i know it actually works. how can i visibly test the design on the DE2 board to make sure it works (E.G make some LEDs flash, something of that nature) ANY HELP WILL BE GREATLY APPRECIATED.

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    You can't test a filter by "flashing a LED", I think. Normally I would expect a project specification to define reasonable test methods. If you don't have suitable hardware interfaces as source and sink of analog data (ADC/DAC), you can generate stimulation data from a RAM or ROM table and acquire the filter output with SignalTap.

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Normally you create a filter math. model that takes in same random input (or actual expected signal) to produce reference output that need be compared with design data captured in some way.

    You will need to be familiar with bit accurate modelling.

    As a short cut for FIR, you may pass just an impulse input then you should get your coeffs out.

    The impulse input is one sample at high value with zeros after it. You need to repeat that from time to time and check your outputs. The coeffs will be scaled out depending on your sample value. This is a good test but is not best. Best is a random data.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    14 years ago

    --- Quote Start ---

    You can't test a filter by "flashing a LED", I think. Normally I would expect a project specification to define reasonable test methods. If you don't have suitable hardware interfaces as source and sink of analog data (ADC/DAC), you can generate stimulation data from a RAM or ROM table and acquire the filter output with SignalTap.

    --- Quote End ---

    Can you give me more details on this method. i'm new to using the DE2 board so as much detail and references will be very helpful.