TMS320F280039C: ELF Format, CCS, 16Bit Memory Architecture, addresses vs length

Arne Pagel

Part Number: TMS320F280039C

Dear all,

I just came across the point that the addresses in elf file are pointing to 16 Bit Wide entries, while the size is counted in bytes.

So a validity check of section_address + section size <= next_section_address fails.

I wonder of there is a foreseen information in the elf format, or custom information in the ti-ccs elf output to find out this circumstance.

So far the only way I see is to make it dependent on the e_machine type, but maybe there is a more native approach

Any Idea about that?

over 2 years ago

0 Arne Pagel over 2 years ago

Prodigy 30 points

To be added: the compiler I use is 22.6.0.LTS

+1 George Mock over 2 years ago

TI__Guru**** 250340 points

Arne Pagel said:
addresses in elf file are pointing to 16 Bit Wide entries

Correct. Another way to think about it: Addresses on the C28x CPU are counted in terms of 16-bit words, and not 8-bit bytes.

Arne Pagel said:
the size is counted in bytes

Correct.

Arne Pagel said:
a validity check of section_address + section size <= next_section_address fails

Correct. The variables in that expression do not count in terms of the same units. The address counts in terms of 16-bit words and the size counts in terms of 8-bit bytes. One has to be converted to match the other.

Arne Pagel said:
the only way I see is to make it dependent on the e_machine type

Correct. That's the only way I've seen it done.

Thanks and regards,

-George

0 Arne Pagel over 2 years ago in reply to George Mock

Prodigy 30 points

Ok, thanks for clarification,

I found this Doc:

https://www.ti.com/lit/pdf/sprac71

which partially confused me, because it says:

"e_machine: An object file conforming to this specification must have the value EM_C28X (105, 0x69)"
which would refer to MSP430, C2000 is 141 if I am not mistaken.

0 George Mock over 2 years ago in reply to Arne Pagel

TI__Guru**** 250340 points

Arne Pagel said:
C2000 is 141

That is correct. The manual is wrong. I filed the entry EXT_EP-11451 to have the manual corrected. You are welcome to follow it with that link. Thank you for notifying us of the error.

Thanks and regards,

-George

C2000™︎ microcontrollers

C2000 microcontrollers forum

TMS320F280039C: ELF Format, CCS, 16Bit Memory Architecture, addresses vs length