TMS320F28377D: Change variable definition cause the codes run out

Angela Zou

Part Number: TMS320F28377D

Dear expert,

My customer define a variable as: const volatile uint16 Gain_C_PedlFilterCoef = 10U; The software runs properly. Then he change the variable definition into: volatile uint16 Gain_C_PedlFilterCoef = 10U; Then the software will run out.

He look into the .map file, find that the address assigned to the variable is changed from FLASH（0X913DF）to RAM（0X9D03). Please help to find out why the issue occur? Thank you so much.

over 2 years ago

0 Veena Kamath over 2 years ago

TI__Mastermind 32655 points

Yes, the constants (.const section) are loaded to Flash and other .bss and .data variables are loaded to RAM.

Regards,

Veena

0 Angela Zou over 2 years ago in reply to Veena Kamath

TI__Intellectual 1085 points

Hi Veena,

Why the change could cause the codes run out?

0 Ivy Jin over 2 years ago in reply to Veena Kamath

TI__Expert 5205 points

Hi Veena,

If the customer changes the variable definition from const volatile uint16 Gain_C_PedlFilterCoef = 10U to volatile uint16 Gain_C_PedlFilterCoef = 10U, TMS320F28377D will be reset after compilation.

After the customer has tried more, they discover that:
1. Change uint16 to uint32 and the issue does not occur.
2. The compiler does not do o2 optimizations, the issue does not occur.

Could you please give more suggestions and comments? Thanks

Regards,

Ivy

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TMS320F28377D: Change variable definition cause the codes run out