How to use IQmath library in CCS 3.3?

Hi Siyu,

I really don't know why using this library is troubling you. Here's a simplest implementation:

#include<IQmathLib.h> /* Header file for IQ math routine */
_iq in1 out1;
_iq28 in2 out2;
void main(void )
{
in1 = _IQ(1.5);
out1 = _IQdiv(_IQ(1.0), in1);
in2 = _IQ28(1.5);
out2 = _IQ28div(_IQ28(1.0), in2);
}

Yes using global variables would be recommended while using ISRs.

Regards,

Gautam

Hi,

I tried the example project come along with controlSuit and it works well. I think the problem might be using it in ISR.

He, Siyu

Ohk...you're problem now is implementing IQmath in an ISR, right. Can you attach a screenshot of the error while implementing in the same way?

Regards,

Gautam

I defined the

_iq test;

as a global variable before main() in main.C. And define

extern _iq test;

in GloblaVariable.h .

The compilatoin errors is shown below:

Each .C file is detected out a identical error.

He, Siyu

Hi again,

You don't have to include : extern _iq test;  in GloblaVariable.h

Just in main.c is enough.

Also please take into consideration and also what I've been meaning to say since a long time is:

The error _iq is undefined means the compiler is not able to detect this datatype which in turn means that this datatype is inaccessible.

Did you try declaring _iq  in the ISR itself?

Regards,

Gautam

Hi,

(1)I defined extern _iq test in GlabalVariable.h and added #include "IQmathLib.h" in DefaultIsr.C. The compilation went through. I am trying to redefine the GLOBAL_Q and MATH_TYPE, it seems like they should be defined in IQmathLib.h not in main.C. Am I right?

(2)The computation results is still in IQ format, before I use it to assign to output, do I need to convert it back to float?

(3)I added test and _IQ(test) in watch window to view value. It turns out that the test would change but the_IQ(test) is not changed, I have to re-type _IQ(test) into watch window to refresh. How to do with it?

(4)If I want to do  _iq20 test = IQdiv4(_iq15(A)), do need to converter the right side to _iq20, _iq20 test = _iq20(IQdiv4(_iq15(A)))?

He, Siyu

Hi,

As per my info, for computations datatypes have to be same for eg. if you define _iq20 based variables; computation variables and the result variable has to be of type _iq20.

Regards,

Gautam