IQmath from F28027 to F28069

vladimir vladimir1

Other Parts Discussed in Thread: TMS320F28027, TMS320F28069, MOTORWARE

Hello. I have working program for vector control on TMS320F28027 and i want convert all calculations on TMS320F28069.

Simple code:
 
Asin=_IQ19sin(_IQ19(6.28));
  Acos=_IQ19cos(_IQ19(6.28));

  Asqrt=_IQ19sqrt(_IQ19(4));
  Ampy=_IQ19mpy(_IQ19(10),_IQ19(2));
  Adiv=_IQ19div(_IQ19(10),_IQ19(2));

works on F28027 :sin(6.28)=-0.0032, Asqrt=5 etc...

but when i placed it to F28069 i was very surprised:

Asin=_IQ19sin(2*pi)=-0.7825889587

Acos=_IQ19cos(2*pi)=1.102172852

Asqrt=_IQ19sqrt(4)=-508.0003605;!!!!!

etc. Only _IQ19mpy works...

What I did wrong?My actions:

1. added iqmathlib.h

2. added "rts2800_fpu32.lib"

3. added "IQmath_fpu32.lib"

4. added "rts2800_fpu32_fast_supplement.lib"

5. 28069.cmd file:

FPUTABLES : origin = 0x3FD860, length = 0x0006A0 /* FPU Tables in Boot ROM */
IQTABLES : origin = 0x3FDF00, length = 0x000B50 /* IQ Math Tables in Boot ROM */
IQTABLES2 : origin = 0x3FEA50, length = 0x00008C /* IQ Math Tables in Boot ROM */
IQTABLES3 : origin = 0x3FEADC, length = 0x0000AA /* IQ Math Tables in Boot ROM */

/* Allocate IQ math areas: */
IQmath : > FLASHA, PAGE = 0 /* Math Code */
IQmathTables : > IQTABLES, PAGE = 0, TYPE = NOLOAD

/* Allocate FPU math areas: */
FPUmathTables : > FPUTABLES, PAGE = 0, TYPE = NOLOAD

6. in iqmathlib.h strings:

#define FLOAT_MATH 1
#define IQ_MATH 0

#ifndef MATH_TYPE
#define MATH_TYPE IQ_MATH
#endif

7. Compiler opt:

-v28 -ml -mt --cla_support=cla0 --float_support=fpu32 --vcu_support=vcu0

over 10 years ago

0 vladimir vladimir1 over 10 years ago

Intellectual 565 points

0 Vishal_Coelho over 10 years ago

TI__Mastermind 20850 points

Hi,

IF you wish to keep the IQMath library in your project but use floating point arguments you need to set MATH_TYPE to FLOAT_MATH in the IQmathLib.h header file. If you left it to IQ_MATH, it will expect all the arguments to be fixedpoint and scaled correctly.

By doing _IQ19sqrt(4) you are trying to do _IQ19sqrt(0x00000004), but IQ19sqrt expects its argument to be in the IQ19 format. So,
_IQ19sqrt(_IQ19(4)) you are effectively casting the argument 4 to IQ19 i.e. 4 * 2^19 = 2097152 and then calling the IQ19sqrt() on it. If you skip the typecast you get the wrong answer.

Similarly, _IQ19cos(_IQ19(6.28)) is actually _IQ19cos( floor(6.28 x 2^19)) or _IQ19cos(3292528).

0 vladimir vladimir1 over 10 years ago in reply to Vishal_Coelho

Intellectual 565 points

but i did it

for example
Asqrt=_IQ19sqrt(_IQ19(4))
Result: -508.0003605

i trying work with 28069 using only fixed math.

added to iqmathlib.h

#define   MATH_TYPE      IQ_MATH

changed

#define FLOAT_MATH 0 /
#define IQ_MATH 1

---without changes...

I use IQmath_fpu32.lib. May be a problem with this? I treed built with IQmath.lib, but was a lot of errors:

file "../IQmath.lib<IQ19cos.obj>" specifies ISA revision "C2800", which Vector_28069 C/C++ Problem

Description Resource Path Location Type
file "../IQmath.lib<IQ19div.obj>" specifies ISA revision "C2800", which Vector_28069 C/C++ Problem

etc

May be i must use IQmath.lib?

0 Vishal_Coelho over 10 years ago in reply to vladimir vladimir1

TI__Mastermind 20850 points

You dont have to change the values of FLOAT_MATH and IQ_MATH, you only have to change the math type

#define FLOAT_MATH 1
#define IQ_MATH 0

#ifndef MATH_TYPE
#define MATH_TYPE FLOAT_MATH
#endif

Now, it looks like you have --fpu_support=fpu32 turned on in your project settings, which is why you are getting the error of conflicting ISAs (Instruction Set Architecture). Use IQmath_fpu32.lib instead of IQmath.lib and that error goes away, and everything should work.

0 vladimir vladimir1 over 10 years ago in reply to Vishal_Coelho

Intellectual 565 points

Let me ask the question differently. I have a project that works with a fixed point. I want to transfer the project to another controller (TMS2802x to TMS2806x). And wish he also worked with a fixed point, not floating. What steps should I make? My current actions:
1, add IQmathlib.h
2. add IQmath.lib
3. change -fpu_support=softlib. Results:
a) _IQ19sin(0.5236)=-0.9569416046, but sin(pi/6)=0.5
b)_IQ19sqrt(5.3)=-508.0003605, but sqrt(5.3)=+2.3.What am i doing wrong?

0 Vishal_Coelho over 10 years ago in reply to vladimir vladimir1

TI__Mastermind 20850 points

Ok, do steps 1 and 2, but not 3. You want to turn off any fpu_support. If you want to work in fixed point set MATH_TYPE to IQ_MATH

0 Feng CHEN over 9 years ago in reply to Vishal_Coelho

Expert 1670 points

IQmath usage problem on F28069M

Now, I am working on F28069M and want to implement FOC for motor control.

When using math functions as below, the result seems abnormal.

Simple code:

x2 = _IQ29(0.25*pi); //pi = 3.1415

alpha = _IQ29sin(x2);

beta = _IQ29toF(alpha);

the result is below after running it:

x2 = 421657408

alpha = -473477883

beta = -0.8819212

Obviously the result of alpha is wrong.

And I try function of _IQ29cos(), the result is still wrong. But other functions (such as _IQ29tan())are correct.

Following is my setting:

1. added iqmathlib.h

2. added "rts2800_fpu32.lib"

3. added "IQmath_fpu32.lib"

4. added "rts2800_fpu32_fast_supplement.lib"

5. #define MATH_TYPE IQ_MATH

6. Compiler opt:

-v28 -ml -mt --cla_support=cla0 --float_support=fpu32 --vcu_support=vcu0

Could you help me support on this issue? Looking forward to your reply. Thank you.

0 Vishal_Coelho over 9 years ago in reply to Feng CHEN

TI__Mastermind 20850 points

Hi,

It sounds like the sine table is not in the right place. Can you check the address of the IQTable in the linker command file and match them up to what is provided in the F28069 TRM

Its in chapter 2, here is a snippet

0 Vishal_Coelho over 9 years ago in reply to Vishal_Coelho

TI__Mastermind 20850 points

Actually, since you have an instaspin part the IQTABLES are located at

   IQTABLES    : origin = 0x3FDC30, length = 0x000B50    /* IQ Math Tables in Boot ROM */
   IQTABLES2   : origin = 0x3FE780, length = 0x00008C    /* IQ Math Tables in Boot ROM */
   IQTABLES3   : origin = 0x3FE80C, length = 0x0000AA	 /* IQ Math Tables in Boot ROM */

You can get the right linker command files from motorware (C:\ti\motorware\motorware_1_01_00_16\sw\ide\ccs\cmd\f2806x)

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IQmath from F28027 to F28069