• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 82 subscribers
  • Views 217 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.

TMS320F28335: Writing to Flash memory

Prashant Achari
Prodigy 90 points
Part Number: TMS320F28335


Tool/software:

In my current project, I need to test the FLASH memory as part of the Power-On Self-Test (POST). Based on my research, the typical approach involves erasing memory sections, writing known data, reading it back, and verifying the integrity. However, I’m concerned that performing this test might inadvertently lock the device. Could anyone suggest a safe and reliable method to proceed?

Regards

Prashant V Achari

  • 0
    TI__Guru* 81560 points

    Prashant,

    I'll give some more detail on the locking device aspect below; but for flash memories many customer embed a checksum of the flash contents when they program the flash, and then this could be checked as part of a POST vs re-programming the flash on each power up.  Also, if you intend to do a complete erase/program on every power up, you would have to factor in that you have to re-download your code to the flash from some external source on each power up, which likely isn't practical.  Finally there is a 50k W/E limit on the flash for its lifetime, so this would need to be understood as well.

    Under normal operating conditions, erasing and programming the main arrays will not lock the device.  It is only if the erase/programming is interrupted that there can be an issue here; and it is under a specific set of circumstances.  The passwords on this device are located in the last 8 words of flash sector A.  If the flash procedure is interrupted(this could be from unplanned XRSn, or power droop/loss) while sector A or sector H(this is sector A's balanced sector), then there could potentially be values that are non 0xFFFF programmed into these regions locking the device.  If you are not W/E Sector A or H, there should be low to no risk in accidentally locking the device, even if the flash operation is interrupted unexpectedly, so there is that option as well, if you are still concerned about accidentally locking the device.

    Best,

    Matthew