Embedded board with good support out of the box?

Mr. Andrei Chichak groups at chichak.ca
Fri May 22 18:28:29 UTC 2015


On 2015-May-22, at 11:23 AM, Steve B <sbattazzo at gmail.com> wrote:

> Is there some kind of file system support ready to go so I can log all of my data as well?

I haven’t managed to wrap my head around the filesystem/SD card system in RTEMS yet. The projects that I have been working on, until recently, didn’t need logging. One project I did do that used SD cards, I used a chunk of code called FatFS that “worked”. On the STM32F4, people are getting a blazing 4MB/second write speed using a class 10 card and the SD 4-bit interface (beware of the specs, class 10 can actually mean 10MB/sec read, but 0.5MB/sec write - thanks Kingston). That was about half of what our project required.

Once I get a stable implementation (ST keeps changing that chunk of their SD code and it’s currently pretty busted) and I find a reasonable example of the RTEMS filesystem + I2C/SPI/SD system, I expect that putting in a logging file system would be pretty quick.

Interesting bit:
One of our customers called up saying that the equipment we made was having errors after running for 2.5 years. It turns out that they were logging data once per second, didn’t fill up the SD cards, but the directory on the card (FAT32) was being erased and written about once every 8 - 16 seconds, and it wore out the sector of the card that contained the directory. FAT is not a good long term logging file system, but it can be read by a peecee.

A


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