CCS/CCSTUDIO-C2000: How to give filtered signal to PID controller as reference ?

Hello Ananda,

You should take a look at the DCL - Digital Control Library - www.ti.com/.../C2000-DIGITAL-CONTROL-LIBRARY .

HTH,
John W.

In reply to John Westmoreland43:

My filtered signal is in the array format of length 50.And i want that signal convert into float rk ,which is my reference to pid. I can't write rk=AdcBufFiltered[index]. then rk is choose any value from the array.how to resolve that problem.

In reply to Ananda Hange:

It looks like the filtered signal is in IQ format, so you can use the IQ to float conversion from that library:

rk=_IQtoF(AdcBufFiltered[index]);

You should also typecast the ADC results to float. Your first assignment, the current sensor reading, would look like this:

I_sensor_FC =(float) SampleTable[i] * 7.326007326e-4 - IDC_offset;

On last thing; where you are assigning float constants it's better to place an 'f' at the end to make it unambiguous to the compiler. For example:

float IDC_offset=0.0f, ...

Regards,

Richard

In reply to Richard Poley:

Filter.cLPF2.cLPF2.cIQmathLib.hwhen i use this line rk = _IQtoF(AdcBufFilter[index]); i got errors as follows,

Description Resource Path Location Type

unresolved symbol __IQ24toF, first referenced in ./LPF1.obj EV1 C/C++ Problem

Description Resource Path Location Type

<a href="file:/c:/ti/ccsv7/tools/compiler/dmed/HTML/10234.html">#10234-D</a>  unresolved symbols remain EV1 C/C++ Problem

Description Resource Path Location Type

#10010 errors encountered during linking; "EV1.out" not built EV1 C/C++ Problem

I attached file LPF2.c which is main file and filter.c and IQmathlib.h file .

In reply to Ananda Hange:

It sounds like you haven't linked IQmath.lib. Check section 3.5 of the IQ math Quick Start guide.

Which device are you using?

Regards,

Richard

In reply to Richard Poley:

Yeah I hadn't link that IQmath.lib .Even if i link that I got some new error as follows,

Description Resource Path Location Type
<a href="file:/c:/ti/ccsv7/tools/compiler/dmed/HTML/16008.html">#16008-D</a> file "../IQmath.lib<IQ24toF.obj>" specifies ISA revision "C2800", which is not compatible with ISA revision "C28FPU32" specified in a previous file or on the command line EV1 C/C++ Problem.

I'm using Delfino f28335 of c2000 famiy.

In reply to Ananda Hange:

I think this is because you've built for the FPU32 but are linking the fixed point version of IQmath.  Try linking "IQmath_fpu32.lib" instead of "IQmath.lib".  Both are in the \lib sub-directory in C2000Ware.

Regards,

Richard

In reply to Richard Poley:

Hello Ananda,

Just wondering - were you able to resolve your issue?

Did Richard's last reply do the trick for you?

Thanks,
John W.