TransferFunction Block

Altair Forum User
Altair Forum User
Altair Employee
edited November 2020 in Community Q&A

Submitted by ctedie on Wed, 07/27/2011 - 20:47 

Hi,
I have troubles to use the Transfert function block with a TMS320F28035.
I try to filter a signal with a low-pass filter.
It runs good in simulation mode, but when I compile the block and then run the vissim diagram of my compilated block I have nothing in the filtered output.
Could you help me?
I join the diagram I use

Unable to find an attachment - read this blog

Answers

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited November 2020

    Submitted by Anders89 on Fri, 07/29/2011 - 00:17.

    Because your cutoff frequency is 5 orders of magnitude lower than the sampling frequency there are some small values in the coefficients. This requires use of 32-bit precision in the fixed point filter (you were using 16-bit). Here is an example of a run showing good agreement between 

     

    slowFilterOutputCompare.png

     

    simulation on the PC and results from the embedded target. Please find the modified diagram attached below.

    Unable to find an attachment - read this blog