Function Moving to Ram from Flash memory, But why it takes almost same execution time?

Pritesh Gohil

Other Parts Discussed in Thread: TMS320F28335, CONTROLSUITE

Hi,

I'm Using TMS320F28335 Experiment kit In that i written code for some application having 4 to 5 source file.

I'm loading entire code into the flash memory, also i moved time critical function to RAM using "#pragma CODE_SECTION(fun_name, "ramfuncs");" After moving 3 to 4 function i debug the code and I checked .Map file of the project to verify the allocation of these function. Its Working fine and i crosschecked with the "CCS->View-> Memory Browser" and this is also shows the proper allocation of the function.

Upto this point everything is fine But when i start execution to check function Execution time its just reduces to 1 us.

As per my program "RunABCDQConversion();" function will take time as follows:

code loaded into the ram = 2.5us
code loaded into the Flash (without #Pragma) = 5.5 us
code loaded into the Flash (without #Pragma) = 4.5 us

so after moving to ram Execution time reduces to 1us instead of 2.5us. This is true for all the function which moved to ram.

So what can be the solution to this problem? and why it takes almost same execution time? How to reduces it to almost time i.e. taken by RAM?

Thanks,

pxl_29

over 10 years ago

0 Gautam Iyer over 10 years ago

Guru 192875 points

Hi,

This 2.5us that you're talking about, is this for the complete program execution or just a function?

Regards,
Gautam

0 Pritesh Gohil over 10 years ago in reply to Gautam Iyer

Intellectual 265 points

code loaded into the ram = 2.5us
code loaded into the Flash (without #Pragma) = 5.5 us
code loaded into the Flash (with #Pragma) = 4.5 us

This all i'm talking about for function execution time only. Everything is Set well but i could not figure out that even though function moved and located to RAM then why its taking more function execution time.

Cheers,

pxl_29

0 Mitja Nemec over 10 years ago in reply to Pritesh Gohil

Genius 5885 points

You have to move also the functions, that your function is calling.

0 Pritesh Gohil over 10 years ago in reply to Mitja Nemec

Intellectual 265 points

hi Mitja Nemec,

I already moved those functions, that my function is calling. Its also placed properly in RAM. Do i need to change any internal or Program setting?

0 Gautam Iyer over 10 years ago in reply to Pritesh Gohil

Guru 192875 points

Did you refer: www.ti.com/.../spraau8.pdf

0 Pritesh Gohil over 10 years ago in reply to Gautam Iyer

Intellectual 265 points

Yes Gautam,

I refer to this document previously. everything seems perfact except one doubt.

I'm using 320F28335, and i can not find a SectionCopy asm file like "DSP28xxx_SectionCopy_nonBIOS.asm" this which mentioned in www.ti.com/.../spraau8.pdf.

So is it necessary to add this file and if yes then where it is located, i double checked the "controlSUITE\device_support\f2833x " header and common folder.

Thank You,

Pritesh Gohil

0 Gautam Iyer over 10 years ago in reply to Pritesh Gohil

Guru 192875 points

Pritesh Gohil said:
So is it necessary to add this file and if yes then where it is located, i double checked the "controlSUITE\device_support\f2833x " header and common folder.

Not Required. Though your case seems pretty odd. Lets wait for what TIers have to say.

0 Vamsi Gudivada over 10 years ago in reply to Pritesh Gohil

TI__Guru* 87155 points

Pritesh,

Do you have any interrupts enabled? May be some interrupt service routine is getting executed in between?

Thanks and regards,
Vamsi

0 Pritesh Gohil over 10 years ago in reply to Vamsi Gudivada

Intellectual 265 points

Hi Vamsi,

I have tested many functions, so for the very first time i was getting this issue and i resolved it immediately.
So for function execution time testing i disabled all the interrupts because it is not required at all.

Thanks,
Priresh Gohil

0 Mitja Nemec over 10 years ago in reply to Pritesh Gohil

Genius 5885 points

Did you also move RTS library (or IQmath if you ar using it) functions to RAM? From the name of the function I assume you are at least using "sin" and "cos" functions. And probably also a division (integer or float). Enable compiler options to keep assembly intelisting files (--src_interlist) and look for all the LCR instrucions in your functions. This is one way to find out which functions is your code calling. If you also enable placing each function in its subsection (--gen_func_subsections=on) you can easily check .map file to see in which section is which function.

0 Janos Szeman over 10 years ago

Intellectual 995 points

Hi Pritesh,

Do you use the same optimization level on the flash project?

Janos

0 Pritesh Gohil over 10 years ago in reply to Mitja Nemec

Intellectual 265 points

Hi Mitja,

Thank you so much for your suggestion,

You are right, Actually I'm using "RTS library" and i didn't moved it to RAM.

Because of this only its taking the same execution time. Right now i'm trying to move Fast RTS Lib to ram. I will update it based on the results i'll get.

Thanks,

Pritesh Gohil

0 Pritesh Gohil over 10 years ago in reply to Mitja Nemec

Intellectual 265 points

Hi Mitja,
I Solved the problem, As You are right the issue was only with the library which i didn't moved to ram.
After moving i also monitored with assembly code and now every thing works well.
Thank you again for your help.

Thanks and regards
Pritesh Gohil

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Function Moving to Ram from Flash memory, But why it takes almost same execution time?