TransferFunction Block

Altair Forum User

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

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Altair Forum User

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 

 

 

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

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