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Unread 09-01-2014, 14:05
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Re: CRio Flash Memory

Quote:
Originally Posted by adlasa View Post
It is in regard to writing images to the CRio memory from a camera within a While Loop


Is this something to be concerned about? I have a hard time believing FIRST would right their code in a dangerous way by default given that a lot of teams may be inclined to just copy and paste.
Yes it is something to be concerned about. However, FIRST did not enable the image writing by default. You must uncomment the image write. They give the appropriate warning if you do uncomment the image write.


Quote:
Originally Posted by E Dawg View Post
Using it is okay, just be careful. It shouldn't permanently damage your cRIO, but it can definitely eat up flash memory (and slow down your connection).
This is incorrect. You can permanently damage the flash memory in the cRIO. Like Tom and the Tutorial said, do not write more often then needed.

From the cRIO-FRC II datasheet

Quote:
For information about the life span of the nonvolatile memory and about best practices for using nonvolatile memory, go to ni.com/info
and enter the Info Code SSDBP.
This leads to Understanding and Extending the Life of my Solid-State Drive, which states the following

Quote:
However, solid-state drives have a limited number of write/erase cycles. This disadvantage is the primary focus of this white paper. The physical cells of SSDs wear out over time.
In practice, with the wear leveling that the cRIO performs, I would guess that each team could get at least 1 million 8k writes. Given that an image is likely larger then 8k, if you wrote an image every 20ms, the cRIO flash memory could fail in around 100 hours. But, it's easy to avoid that. Even reducing that rate to once a second makes it so that a team would never run into an issue.

Last edited by Joe Ross : 09-01-2014 at 14:11.