TMS320C6746: About the definition of global variables

Yoshiaki Suzuki

Part Number: TMS320C6746

Hi all.
I am defining global variables in a single header file.
When I look at the variables in memory after compiling, they are not in the order I defined them.
There is a device configuration item in the global variables.
If these items are not lined up in the order in which they are defined, problems will occur in the program.
In the case of the combination of C2000 & CCS7, the items were replaced to match the addresses in multiples of 4 in the case of 32bit data, but other than that, they were in the order defined. (The porting was done from 5509A to 6746)

Is there some setting I need to do to make it in the defined order?

Thanks in advance.
Suzuki

over 4 years ago

0 Jianzhong Xu over 4 years ago

TI__Guru 59425 points

Hi Suzuki,

Global variables defined in your code are not necessarily placed in the memory in the order they are defined in the code. If you need to maintain a certain order in the memory, you'll have to do that in your code. For example, you can include them in a same data structure.

Regards,

Jianzhong

0 Yoshiaki Suzuki over 4 years ago in reply to Jianzhong Xu

Prodigy 230 points

Hi Jianzhong.

If you make it a structure, it will be a lot of work to modify the program.
Can't you specify this in the compiler settings?

Thank you for your time.
Suzuki

0 Jianzhong Xu over 4 years ago in reply to Yoshiaki Suzuki

TI__Guru 59425 points

Hi Suzuki,

Yes, you can use compiler pragma SET_DATA_SECTION to specify a section for each global variable, and then place the sections into memory in the linker command file. Please refer to the following documents:

1. How to use compiler pragmas: TMS320C6000 Optimizing Compiler User's Guide

2. How to place memory sections: TI Linker Command File Primer

Regards,

Jianzhong

0 Yoshiaki Suzuki over 4 years ago in reply to Jianzhong Xu

Prodigy 230 points

Hi Jianzhong.

With your guidance I was able to achieve my goal.

Thank you very much.
Suzuki

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TMS320C6746: About the definition of global variables