CCS/CCSTUDIO: How to use .cmd to fix a whole .c code file compiling result into a fixed flash address?

Intellectual 1980 points

Part Number: CCSTUDIO
Other Parts Discussed in Thread: CC1310

Tool/software: Code Composer Studio

Hi Team,

My customer has a request to fix a whole .c code file compiling result into a fixed flash address, I think it should be done in the .cmd file.

Any examples or formats of .cmd file modification I can reference for this use case? I suppose it should be in SECTION / GROUP define in .cmd file, am I right?

The TI device is CC1310, but I believe it is not directly relevant, it could be any devices.

Thanks!

over 4 years ago

0 George Mock over 4 years ago

TI__Guru**** 244930 points

I want restate the problem, to be sure I understand it correctly. Your customer wants to allocate all the functions from one C source file to a specific address in flash memory. Is that correct? For now, I presume it is.

For general background on the linker command file, please read the article Linker Command File Primer.

There is more than one way to do it. I think this is the most straightforward.

In the linker command file, in the SECTIONS directive, have an entry similar to ...

    special_output_section
    {
        name_of_file.obj(.text)
    } > SPECIAL_MEMORY_RANGE

This forms an output section named special_output_section. It contains one input section, which is the .text input section from the object file name_of_file.obj. It is allocated to an address in the SPECIAL_MEMORY_RANGE. The SPECIAL_MEMORY_RANGE is specified in the MEMORY directive (not shown in this example). If desired, replace SPECIAL_MEMORY_RANGE with a hard coded address such as 0x4000.

Thanks and regards,

-George

0 YZ over 4 years ago in reply to George Mock

TI__Intellectual 1980 points

Hi George,

To be more accurate, not only the functions, but also all the variables in one C source file to a specific address in flash memory.

I tried something, from output .map file looks it works: put sensor.c functions & variables into flash address starts at FLASH_SENSOR, and the length is 0x2000 (defined at the beginning of .cmd file, not pasted here)

    GROUP
    {
    	sensor_code {sensor.obj}
    } LOAD = FLASH_SENSOR

Does it look OK to you? Anything else to be aware of?

Thanks!

0 George Mock over 4 years ago in reply to YZ

TI__Guru**** 244930 points

That works, but this is cleaner ...

sensor_code
{
   sensor.obj
} > FLASH_SENSOR

This creates an output section named sensor_code. It is made up of all the input sections, both code and data, in the object file sensor.obj. It is allocated to an address in the memory range FLASH_SENSOR.

Thanks and regards,

-George

0 Chester Gillon over 4 years ago in reply to YZ

Guru 92251 points

Yan said:
I tried something, from output .map file looks it works: put sensor.c functions & variables into flash address starts at FLASH_SENSOR

Won't placing writable variables into FLASH will cause the program to fail to write to the variables?

Code Composer Studio™︎

Code Composer Studio forum

CCS/CCSTUDIO: How to use .cmd to fix a whole .c code file compiling result into a fixed flash address?