"Proper" procedure for starting and stopping loggi

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Alex W
Posts: 41
Joined: Tue Apr 16, 2013 5:57 pm
Location: Bozeman, MT

"Proper" procedure for starting and stopping loggi

Post by Alex W »

Is there a correct way to go about starting and stopping a log to ensure that it gets written to the SD card?

Things like
"insert the SD card with the unit powered off"
"wait 30 seconds after powering on to start logging"
"wait 30 seconds after stopping the log to power off"
"do not remove the SD card with the unit powered on"
etc, etc

On several occasions in my testing I have had a log fail to write to the SD card, and it always seemed to be related to doing (or not doing) some combination of the above. I have not done enough testing to confirm that any one of these things was at fault, but it seemed to be when I did those sorts of things. The data wasn't corrupt or anything, there was just no file written to the card at all. In no case did the red error light come on, and the logging LED always flashed as expected. I never removed the card while actually logging.

Perhaps a future version of the firmware could make better use of the logging and error lights to visually confirm that data IS in fact being written to the card, and if there is a time required after logging stops to "finish" writing, the logging light could continue to blink until it is safe to remove the card?

GTIspirit
Posts: 249
Joined: Wed Jan 09, 2013 11:20 am
Location: SE Michigan

Re: "Proper" procedure for starting and stopping l

Post by GTIspirit »

Alex W wrote:Is there a correct way to go about starting and stopping a log to ensure that it gets written to the SD card?

Things like
"insert the SD card with the unit powered off"
"wait 30 seconds after powering on to start logging"
"wait 30 seconds after stopping the log to power off"
"do not remove the SD card with the unit powered on"
etc, etc

On several occasions in my testing I have had a log fail to write to the SD card, and it always seemed to be related to doing (or not doing) some combination of the above.....
I had the same thing happen to me while testing this weekend. I stuck the SD card in with the unit powered up, pressed start logging and then after 20s or so pressed stop logging. I think I probably popped the SD card out too soon because it was empty when I stuck it in my computer to read. It didn't happen to me again after I made a point to wait longer after stopping the logging.

So maybe there are some user requirements we need to be aware of?

brentp
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Joined: Wed Jan 24, 2007 6:36 am

Post by brentp »

it should be documented (but maybe not) that the red LED is a general error status light. Currently it will illuminate if there is a problem writing to the SD card. Generally speaking the system should be available for writing to SD card right after powerup- the bootup time is minimal.

If you are able to reliably reproduce this issue please post it here and we'll take a look. of course, we will keep an eye out for it too. Also consider testing with different cards; some cards take longer to initialize and may surpass the timeout period built into the the initialization routines.

* You can remove the SD card with the unit powered up.
* The logging flushes periodically (on a minute interval) so in theory, you can even remove the card while logging and capture what was last flushed to disk.
* You should be able to remove the card immediately after logging stops.

Please do experiment to verify this for yourself, and report back anything noteworthy. Now that RaceCapture/Pro is in so many more hands the lurking firmware bugs will be teased out and fixed.

Thanks!
Brent Picasso
CEO and Founder, Autosport Labs
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Alex W
Posts: 41
Joined: Tue Apr 16, 2013 5:57 pm
Location: Bozeman, MT

Post by Alex W »

As is typically the case, I can't get it to repeat the problem now that I am looking for it. I have tried perhaps a dozen times in the last few minutes, and breaking all of the rules that I suggested in my first post, and the closest I was able to get was by removing the card in the middle of logging after about 15 seconds of logging, in which case I got a 0kb blank file, but I still GOT a file, which is more than I got when it failed before. Otherwise, I have inserted and removed the card with the unit on, started logging within a second or two of powering the unit on, and stopped logging and then immediately (within a second or two) removed the card, and every time it wrote a file as it should. I even tried unplugging the power while logging (just over a minute into a log) and ended up with about 67 seconds logged to file, which seemed exactly right.

A little frustrating, because it happened multiple times in previous testing. Perhaps I totally mis-guessed at what was causing it and it was something else entirely, because my suspected causes aren't delivering at all.

sbarton
Posts: 94
Joined: Mon Mar 11, 2013 5:45 pm
Location: NJ
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Post by sbarton »

Does RCP need to create a directory structure when a card is first installed? Maybe the issue is that when first installing a new SD card you need to wait a while to before recording? After the first successful recording you then wouldn't have to worry about it and can start faster?

-Scott
Duct Tape Motorsports
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