CCS/TMS320F28377S: const key word for storing array in flash

sam kh

Part Number: TMS320F28377S
Other Parts Discussed in Thread: C2000WARE, CONTROLSUITE

Tool/software: Code Composer Studio

I want to store an int array (table) and an array of struct in flash memory. For this const keyword (as given in section 6.6.1 TMS320C28x Optimizing C/C++ Compiler) is used or I have to use "#pragma DATA_SECTION" given in TMS320C28x Optimizing C/C++ Compiler?

section 6.10.7 The DATA_SECTION Pragma??

Ex- const unsigned int array[10]={1,2,3,4,5,6,7,8,9,0}; //This is stored in flash or ram ??

similarly for array of struct

typedef struct test{

int a;

float b;

}test;

const test array[5]={ //Is this is stored in flash ????

{1, 10.1},

{2, 10.2}

};

over 4 years ago

0 Rajaravi Krishna Katta over 4 years ago

TI__Expert 6795 points

Hi Sam,

You can use any approach

For a separate sections use pragma

FUNC_PTR : > FLASH

Or use the default const section

.const : > FLASH

Please refer http://software-dl.ti.com/ccs/esd/documents/sdto_cgt_Linker-Command-File-Primer.html

Regards,

Katta

0 sam kh over 4 years ago in reply to Rajaravi Krishna Katta

Expert 1635 points

You mean for storing array table I have to make change in the linker file. Declaring a table constant, using "const" in c code is not sufficient ??

0 Rajaravi Krishna Katta over 4 years ago in reply to sam kh

TI__Expert 6795 points

Yes. Please refer Flash based linker command files in c2000ware for reference at \C2000Ware_path\device_support\f2837xs\common\cmd\

Thanks, Katta

0 sam kh over 4 years ago in reply to Rajaravi Krishna Katta

Expert 1635 points

I made changes in the linker file by putting ".const : > FLASH"

But I am getting this result. As you can see the value of initialized data and uninitialized data is changed but no change in the code section. I think the data should move to the code section but it is still in RAM.

Before changing in linker file:-

Module code initialized data uninitialized data

Total: 55580 19674 5850

After change:-

Module code initialized data uninitialized data

Total: 55580 19671 6426

0 Rajaravi Krishna Katta over 4 years ago in reply to sam kh

TI__Expert 6795 points

Please attach your linker command file and .map file.

0 sam kh over 4 years ago in reply to Rajaravi Krishna Katta

Expert 1635 points

Sorry, I made some mistake. When I place the ".const : > FLASF ", I got this error.

"program will not fit into available memory. run placement with

alignment/blocking fails for section ".const" size 0 page 1"

I can't post my map file publicly. Can you share any other link, on which I can send my files?

And this is my linker file:-

MEMORY

{
PAGE 0 : /* Program Memory */
/* Memory (RAM/FLASH) blocks can be moved to PAGE1 for data allocation */
/* BEGIN is used for the "boot to Flash" bootloader mode */

BEGIN : origin = 0x080000, length = 0x000002
RAMM0 : origin = 0x000122, length = 0x0002DE
RAMD0 : origin = 0x00B000, length = 0x000800
RAMLS0 : origin = 0x008000, length = 0x000800
RAMLS1 : origin = 0x008800, length = 0x000800
RAMLS2 : origin = 0x009000, length = 0x000800
RAMLS3 : origin = 0x009800, length = 0x000800
RAMLS4 : origin = 0x00A000, length = 0x000800
RESET : origin = 0x3FFFC0, length = 0x000002

/* Flash sectors */
FLASHA : origin = 0x080002, length = 0x001FFE /* on-chip Flash */
FLASHB : origin = 0x082000, length = 0x002000 /* on-chip Flash */
FLASHC : origin = 0x084000, length = 0x002000 /* on-chip Flash */
FLASHD : origin = 0x086000, length = 0x002000 /* on-chip Flash */
FLASHE : origin = 0x088000, length = 0x008000 /* on-chip Flash */
FLASHF : origin = 0x090000, length = 0x008000 /* on-chip Flash */
FLASHG : origin = 0x098000, length = 0x008000 /* on-chip Flash */
FLASHH : origin = 0x0A0000, length = 0x008000 /* on-chip Flash */
FLASHI : origin = 0x0A8000, length = 0x008000 /* on-chip Flash */
FLASHJ : origin = 0x0B0000, length = 0x008000 /* on-chip Flash */
FLASHK : origin = 0x0B8000, length = 0x002000 /* on-chip Flash */
FLASHL : origin = 0x0BA000, length = 0x002000 /* on-chip Flash */
FLASHM : origin = 0x0BC000, length = 0x002000 /* on-chip Flash */
FLASHN : origin = 0x0BE000, length = 0x002000 /* on-chip Flash */

PAGE 1 : /* Data Memory */
/* Memory (RAM/FLASH) blocks can be moved to PAGE0 for program allocation */

BOOT_RSVD : origin = 0x000002, length = 0x000120 /* Part of M0, BOOT rom will use this for stack */
RAMM1 : origin = 0x000400, length = 0x000400 /* on-chip RAM block M1 */
RAMD1 : origin = 0x00B800, length = 0x000800

RAMLS5 : origin = 0x00A800, length = 0x000800

RAMGS0 : origin = 0x00C000, length = 0x001000
RAMGS1 : origin = 0x00D000, length = 0x001000
RAMGS2 : origin = 0x00E000, length = 0x001000
RAMGS3 : origin = 0x00F000, length = 0x001000
RAMGS4 : origin = 0x010000, length = 0x001000
RAMGS5 : origin = 0x011000, length = 0x001000
RAMGS6 : origin = 0x012000, length = 0x001000
RAMGS7 : origin = 0x013000, length = 0x001000
RAMGS8 : origin = 0x014000, length = 0x001000
RAMGS9 : origin = 0x015000, length = 0x001000
RAMGS10 : origin = 0x016000, length = 0x001000
RAMGS11 : origin = 0x017000, length = 0x001000

}

SECTIONS
{
/* Allocate program areas: */
.cinit : > FLASHB PAGE = 0, ALIGN(4)
.pinit : > FLASHB, PAGE = 0, ALIGN(4)
.text : >> FLASHB | FLASHC | FLASHD | FLASHE| FLASHF PAGE = 0, ALIGN(4)
codestart : > BEGIN PAGE = 0, ALIGN(4)
ramfuncs : LOAD = FLASHD,
RUN = RAMLS0 | RAMLS1 | RAMLS2 |RAMLS3,
LOAD_START(_RamfuncsLoadStart),
LOAD_SIZE(_RamfuncsLoadSize),
LOAD_END(_RamfuncsLoadEnd),
RUN_START(_RamfuncsRunStart),
RUN_SIZE(_RamfuncsRunSize),
RUN_END(_RamfuncsRunEnd),
PAGE = 0, ALIGN(4)

/* Allocate uninitalized data sections: */
.stack : > RAMM1 PAGE = 1
.ebss : >> RAMLS5 | RAMGS0 | RAMGS1 PAGE = 1
.esysmem : > RAMLS5 PAGE = 1

/* Initalized sections go in Flash */
.econst : >> FLASHF | FLASHG | FLASHH PAGE = 0, ALIGN(4)
.const : > FLASI /*Here I added .const */
.switch : > FLASHB PAGE = 0, ALIGN(4)

.reset : > RESET, PAGE = 0, TYPE = DSECT /* not used, */

#ifdef __TI_COMPILER_VERSION
#if __TI_COMPILER_VERSION >= 15009000
.TI.ramfunc : {} LOAD = FLASHD,
RUN = RAMLS0 | RAMLS1 | RAMLS2 |RAMLS3,
LOAD_START(_RamfuncsLoadStart),
LOAD_SIZE(_RamfuncsLoadSize),
LOAD_END(_RamfuncsLoadEnd),
RUN_START(_RamfuncsRunStart),
RUN_SIZE(_RamfuncsRunSize),
RUN_END(_RamfuncsRunEnd),
PAGE = 0, ALIGN(4)
#endif
#endif

ramgs0 : > RAMGS0, PAGE = 1
ramgs1 : > RAMGS1, PAGE = 1

/* The following section definitions are for SDFM examples */
Filter1_RegsFile : > RAMGS1, PAGE = 1, fill=0x1111
Filter2_RegsFile : > RAMGS2, PAGE = 1, fill=0x2222
Filter3_RegsFile : > RAMGS3, PAGE = 1, fill=0x3333
Filter4_RegsFile : > RAMGS4, PAGE = 1, fill=0x4444
Difference_RegsFile : >RAMGS5, PAGE = 1, fill=0x3333
}

/*
//===========================================================================
// End of file.
//===========================================================================
*/

0 Rajaravi Krishna Katta over 4 years ago in reply to sam kh

TI__Expert 6795 points

It looks like a typo. It should have been

.const : > FLASHI

Thanks,

Katta

0 sam kh over 4 years ago in reply to Rajaravi Krishna Katta

Expert 1635 points

I correct this but still, I get this error.

"C:/ti/controlSUITE/device_support/F2837xS/v190/F2837xS_common/cmd/2837xS_Generic_FLASH_lnk.cmd", line 80: error #10099-D:
program will not fit into available memory. run placement with
alignment/blocking fails for section ".const" size 0 page 1

MEMORY
{
PAGE 0 : /* Program Memory */
/* Memory (RAM/FLASH) blocks can be moved to PAGE1 for data allocation */
/* BEGIN is used for the "boot to Flash" bootloader mode */

PAGE 1 : /* Data Memory */
/* Memory (RAM/FLASH) blocks can be moved to PAGE0 for program allocation */

RAMLS5 : origin = 0x00A800, length = 0x000800

}

/*
//===========================================================================
// End of file.
//===========================================================================
*/

0 Rajaravi Krishna Katta over 4 years ago in reply to sam kh

TI__Expert 6795 points

You need not use .const. Please refer : https://e2e.ti.com/support/microcontrollers/c2000/f/171/t/438147

Looks like it was replaced by .econst in later compilers. Please try and let me know if you find any other issues.

Thanks,

Katta

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CCS/TMS320F28377S: const key word for storing array in flash