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Altera_Forum's avatar
Altera_Forum
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11 years ago

Does changing the Simulink simulation options change the HDL code generation

Hello all,

I am a DSP Builder starter and having read the DSP Builder Advanced Blockset manual I still have some questions.

So is it so that the VHDL code generation is affected by changing the Variable to Fixed-step solver or by changing the Pulse period or width of the data valid pulse generator, etc?

Or is the VHDL generation only dependent on the control and signal blocks?

Thanks in advance.

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    Its only depent on the blocks, but you can only generate VHDL code from fixed step solver.

  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    --- Quote Start ---

    Its only depent on the blocks, but you can only generate VHDL code from fixed step solver.

    --- Quote End ---

    I do not get this...

    How can it be only dependent on blocks but if i change the solver to variable step, no code is generated? So it is actually dependent.

    I opened an DSPBA example (motor control - ALU Folded) and the simulation settings is variable step. Also in the manual it is stated that for ALU folding I need a variable step (for simulation).
  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    Actually, I have not used DSP builder, only Simulink HDL coder. But for that discrete stepping was required.

  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    The solver has no effect on the HDL that DSP Builder generates. However the solver can affect the simulation results, which means when you try to verify your results in Modelsim, you can find spurious simulation mismatches. There are cases where DSP Builder will warn you about this, but probably others where it may not.

    In general, it's best to use the discrete fixed-step solver.
  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    --- Quote Start ---

    The solver has no effect on the HDL that DSP Builder generates. However the solver can affect the simulation results, which means when you try to verify your results in Modelsim, you can find spurious simulation mismatches. There are cases where DSP Builder will warn you about this, but probably others where it may not.

    In general, it's best to use the discrete fixed-step solver.

    --- Quote End ---

    Its been a while since I used the tools, and this makes more sense than my explination.

    Thanks