TMS320F28027F: 28027_IQsampleC can't find 2000Ware files

Roger, 

IQmath.lib is meant to be like an index, it is meant to point to the COFF or the EABI version of the IQMath library depending on your project configuration.

Can you try to use the "IQmath_coff.lib" instead of "IQmath.lib" in your project and try to compile it again?

Best Regards

Siddharth

Hi Siddarth

Thanks for your reply. Sorry, but I can't see how to change the library to IQmath_coff.lib.  Where do I find the location specified in CCS? - I have tried looking everywhere under Project->Properties.

I have also just tried Project->Add files  and added the file IQmath_coff.lib
(which exixsts in C:\ti\C2000Ware_4_01_00_00\libraries\math\IQmath\c28\lib)

but I still get these errors on building the project:

"C:\\Users\\romu\\AppData\\Local\\Temp\\{0611F15C-BDD9-4C67-BF75-5E83DA849543}", line 21: warning:
   cannot resolve archive
   C:/ti/C2000Ware_4_01_00_00/libraries/math/IQmath/c28/lib/IQmath.lib to a
   compatible library, as no input files have been encountered
"C:/ti/C2000Ware_4_01_00_00/libraries/math/IQmath/c28/examples/cmd/28027_IQmath_lnk.cmd", line 72: warning:
   no matching section
"C:/ti/C2000Ware_4_01_00_00/libraries/math/IQmath/c28/examples/cmd/28027_IQmath_lnk.cmd", line 76: warning:
   no matching section
warning: entry-point symbol other than "_c_int00" specified:  "code_start"
Finished building target: "28027_IQsampleC.out"

Can you please help?

Regards,

Roger

Roger, 

The linker command file (28027_IQmath_lnk.cmd) also references IQMath.lib.  Can you update it to use the IQmath_coff.lib. 

Best Regards

Siddharth

Hi Siddarth,

Thanks for the reply. In the file 28027_IQmath_lnk.cmd I could only find the following two references to IQMath.lib and have updated them thus:

IQmath           : > RAML0,      PAGE = 0
   IQmathTables     : > IQTABLES,   PAGE = 0, TYPE = NOLOAD
   IQmathTables2    : > IQTABLES2,  PAGE = 0, TYPE = NOLOAD
   {
        IQmath_coff.lib<IQNexpTable.obj> (IQmathTablesRam)
   }
   IQmathTables3    :> IQTABLES3,   PAGE = 0, type = NOLOAD
   {
       IQmath_coff.lib<IQNasinTable.obj> (IQmathTablesRam)
   }

But I still get the same sort of errors on building:

"C:/ti/C2000Ware_4_01_00_00/libraries/math/IQmath/c28/examples/cmd/28027_IQmath_lnk.cmd" "./CodeStartBranch.obj" "./IQsampleSmall.obj" "../IQmath_coff.lib"  -lrts2800_ml.lib
"C:/ti/C2000Ware_4_01_00_00/libraries/math/IQmath/c28/examples/cmd/28027_IQmath_lnk.cmd", line 72: warning:
   no matching section
"C:/ti/C2000Ware_4_01_00_00/libraries/math/IQmath/c28/examples/cmd/28027_IQmath_lnk.cmd", line 76: warning:
   no matching section
warning: entry-point symbol other than "_c_int00" specified:  "code_start"

I hope you can help..

Regards

Roger

Roger, 

These are only warnings but it is able to generate the binary file . The error related to "undefined symbols" is resolved. Are you still seeing that issue?

Best Regards

Siddharth

Hi Siddharth,

Many thanks.

After restarting CCS I now don’t get (even) any warnings. The program seems to run (as fa as I can see...).

Now I have to work out which parts of this project I need to import into my own project. It all seems a bit complicated – the link command file, etc.!

All I really want to do is look up a sine value given an index. If you know of a simple, cut-down version of this project that can do that, I would be very interested.

What I am actually trying to do is generate a sinewave PWM signal. If you know of any solutions for this processor, I would be very grateful (it seems like a very common thing to want to do!).

Regards

Roger

Roger,

Glad that you were able to get it working. 

The linker command file is needed since it determines where to load the sections of the code to in the memory. 

You can try to retain the code that you code that you need and add it to your project. .

Best Regards

Siddharth  

Hej

OK, thanks. I will try. But I’m afraid don’t have much understanding of the link cmd file.

I am getting a bit confused. I hope the following is not a stupid question:-)

There seem to be two ways of getting a sine function – are they equivalent, or what?

(1) In the example we are using in this thread, the sine function seems to be called using

IQsin(...)

as in the line

Dlog.Xwaveform[i] = tempX = _IQmpy(_IQsin(Step.X), Step.GainX);

also it seems to need the definitions in the file 28027_IQmath_lnk.cmd, like

IQmath           : > RAML0,      PAGE = 0

   IQmathTables     : > IQTABLES,   PAGE = 0, TYPE = NOLOAD

   IQmathTables2    : > IQTABLES2,  PAGE = 0, TYPE = NOLOAD

   {

        IQmath_coff.lib<IQNexpTable.obj> (IQmathTablesRam)

   }

(2) BUT on the other hand I have found several examples in the Forum that just use sine_table[index]  (e.g. thread F28069 sinusoidal PWM generation – OK, but it’s another processor)

E.g.

#include "IQmathLib.h"
#pragma DATA_SECTION(sine_table,"IQmathTables");
_iq30 sine_table[512];

....

sine_table[index]

as in e.g.

EPwm1Regs.CMPA.half.CMPA = EPwm1Regs.TBPRD - _IQsat(_IQ30mpy((sine_table[index]+_IQ30(0.9999))/2, EPwm1Regs.TBPRD),EPwm1Regs.TBPRD,0);

and there is no mention of defining memory locations in a file such as xxx_lnk.cmd

The second solution seems much easier to use (no link cmd table)!

Please could you clarify the difference? Perhaps it is something to do with using the tables in the boot ROM – but instead of what?

Regards

Roger

Roger, 

In the first case, the linker command syntax is used to allocate the tables into the memory section. 

In the second case, #pragma is a compiler directive to create a separate section "sine_table" to allocate the IQMath table

Both are equivalent , only different ways of doing it. 

If you find the second one to be easier, you can use that. 

Best Regards

Siddharth 

Thanks for your reply. Very helpful.

OK, it seems easier to use the second method. (Here, the .lib file is not even mentioned in the .cmd file whether it is _coff or not!)

I am using the ’guts’ of an example I found in the Forum by Frank Borumm

while(1){

        Pwm1Regs.CMPA.half.CMPA = EPwm1Regs.TBPRD - _IQsat(_IQ30mpy((sine_table[index]+_IQ30(0.9999))/2,

        EPwm1Regs.TBPRD),EPwm1Regs.TBPRD,0);

        if (index++ >511) index = 0;

    }

It seems to work, in that the sine value is scaled and assigned to the CMPA register.

But could you please explain:

(1) Why is type conversion from _iq30 (the result of _IQsat(..)) to the register format (Uint16) not necessary?

(2) How can I display values of _iq30 types?  E.g. xx in this:..

_iq30 xx;

....

xx=sine_table[up_down]

The IQ manual IQmath_v15a   states that the Watch window can be used:

Step 3: Viewing IQmath variable

To view a variable in the watch window, simply type the following commands in the watch

window. They will convert the specified "VarName" in IQ format to the equivalent floatingpoint

value:

For C variables:

_IQ(VarName) ; GLOBAL_Q value

but if I type e.g. _IQ(xx)  into the Expressions tab, all I get is a ‘not found’ error in the Watch window.

Regards

Roger

Roger, 

Will forward your query to an IQmath expert.

Best Regards

Siddharth