• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 30 subscribers
  • Views 321 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TM4C129ENCPDT: Errata SSI#03 - can we get more details?

Brian Willoughby18
Intellectual 935 points
Part Number: TM4C129ENCPDT

Would it be possible to get more details on exactly what does not work on SSI1 for Silicon Revision 3 when in Advanced-, Bi-Mode, or Quad-Mode?

I prototyped some firmware which seems to work correctly in Advanced-Mode and Bi-Mode with a Macronix SPI Flash Memory chip attached to the SSI1 port. This is using polled I/O, and it successfully reads back a 1 MB range of data in Bi-Mode that was written using Advanced-Mode.

I'm having a little trouble converting this code from polled I/O to uDMA access, and that's when I discovered Errata SSI#03. However, I'm rather confused since the polled I/O seems to be working just fine. Unless the problems are restricted to uDMA access, I'm left with the impression that the errata isn't very clear about what will or will not work in Advanced- and Bi-Mode on the SSI1 port.

Can anyone shed more light on this subject?

Brian

  • 0
    TI__Guru*** 135355 points
    Hello Brian,

    I have been talking with the team but none of us apps guys were supporting TM4C when this errata was published and we are having a bit of a challenge in tracking down exactly why it was published so broadly.

    Typically if something limited such as the uDMA access was impacted, the errata would be far more constrained. It would state something more like 'do not use SSI1 w/ uDMA for Advanced/Bi-Mode/Quad-Mode' and not just do not use SSI1 for Advanced/Bi-Mode/Quad-Mode period. The broadness makes us quite confident that the issue with SSI1 with those modes is not isolated to just uDMA. Furthermore, we suspect that it also may not present itself in 100% of chips. Errata behaviors can be quirky like that, where only a subset of chips actually exhibit the behavior, and that would explain why your device hasn't had any notable issues.

    Unfortunately unless we are able to uncover any more information, the only thing we can state is that the errata is issued as is and that we cannot recommend using SSI1 under Advanced, Bi-Mode, or Quad-Mode, and to switch to another SSI channel if using those modes to avoid issues with your system.