DASHCam

[Jordan99]

Hi all, not sure if this is in the right place, please move if not! 

I got a new dashcam yesterday because I thought my old one was broken! 

After nearly 2 years of use it started only recording 8 seconds at a time rather the 3 minutes it’s meant to. The new one does the same. Anyone know why this is happening? 

Move been using the sam SD card in my old one for the life of the camera. Thanks! 

[Stoney871]

Check the SD card volume and reformat it, see if that helps.

[Frembrit]

As above...it may have filled up with 'locked' files (because the G sensor is too sensitive) which won't get over-written. You either need to format the card or delete them.

[Jordan99]

I’ve formatted the card in the pc & in the dashcam, still no different?? 

[mjt]

Time for a new card, I suspect. I think the cards have a lifetime defined by the number of write cycles so it's probably life-expired.

[Jordan99]

2 hours ago, mjt said:

Time for a new card, I suspect. I think the cards have a lifetime defined by the number of write cycles so it's probably life-expired.

I’ve ordered a new card now. Hopefully it will sort it. My dash cam does record but every 8 seconds it’s stops recording for about 2 seconds then just repeats the cycle. It’s more annoying because when it stops after the 8 seconds the screen turns off then on again! See it in the corner of my eye every time I drive 

[Micro]

Check your warranty, i had two new sandisks as they apparently had a 10 year warranty!

[Dee_82]

hold your horses guys, one thing you need to be aware of with SD cards is that no two cards are alike. 

also, just because a card is stating its the latest and greatest with mind blowing speeds, doesn't mean it will work.

in fact there is no way of knowing what cards will work in a dash cam. 

ill not bore you all to death with the details but the key performance criteria is not the max read speed, its not even the max write speed, these are both sequential, ie, it records and plays like a vinyl record. the important number is actually the undisclosed RANDOM read / write speeds. due to the nature of a dash cam the data isn't recorded in what you might consider a logical order, its written all over the place in the largest free block of space which means when reading and writing the data is actually accessed from all over the card.

So in short, you are just as likely to have a cheap asda card working then you would a sandisk.

What I'm saying is, not go blowing a shed load of money on the card with the expectation that it will work. it probably wont.  and in actual fact after looking in to dozens of cards from many  manufactures from around the world, you more likely to get it working with a slower older card. note the "more likely" you could also get a blisteringly fast new card that works as well, but that's less likely :)

in answer to your question, the card is the most likely problem unless you have some weird wiring setup or perhaps have a dirty live / ground feeding it

[mattwlkr]

Have you tried it without the SD card to see if it stays on?

Maybe try it at home connected to a PC or mobile charger with the SD card in?

[mjt]

On 07/12/2017 at 10:31 AM, Dee_82 said:

due to the nature of a dash cam the data isn't recorded in what you might consider a logical order, its written all over the place in the largest free block of space

Hi Darren, I realise I'm resurrecting an old thread but, noticing your quote above, it occurred to me that in most cases the writing would be sequential. The manual for my cam recommends reformatting the card every few weeks. Once this is done the entire card will be marked as free so one would expect that the cam will begin writing at the lowest address and then sequentially until the card is full. It then starts overwriting the oldest files but since the new ones are the same length surely they will be replaced in sequential order.

[Dee_82]

nope, that's not the way storage works unfortunately, in terms of the file dates, yes, it will overwrite the oldest one but that might not be recorded in a logical order. Its partly this reason why they tell you to format it (which doesn't actually delete anything, its still all there, you just cant easily see it) stuff gets dumped all over the place.little caches of information that camera uses, settings, temp files, all sorts. Which is why random read / writes are so important, if you think of it like an LP but instead of having it played out in order you might have to skip tracks, forward and back.

[mjt]

Well, that's just the way ordinary PC storage works and why hard drives need defragging but I expected the dashcam would be simpler.

[Lars G]

Question? How have you wired the dash cam into the car? Power socket or piggy back fuse?

If you are using a piggy back fuse installing the piggyback fuse (fuse tap) the wring way round can make the dash cam malfunction as you are describing. I installed one the wrong way round and it kept switching the cam on and off continually for a few seconds at a time. I turned the piggy backfuse round and it worked perfectly. 

Piggy back fuses have to be installed correctly and you will need to know on wha side the fuse is live.

Fuse 85 I think I used.

[GaryPL]

On 06/12/2017 at 4:04 PM, mjt said:

Time for a new card, I suspect. I think the cards have a lifetime defined by the number of write cycles so it's probably life-expired.

I can confirm what you say.  This is precisely the reason why, when installing a SD card in an Android phone, you never select the option to integrate the card into the phone's storage.  Always select portable storage and make do with not being able to have as many apps. Or just pay more for a phone.

SD cards integrated like this, which is just an option for phone makers to skimp on proper amounts of GB, burn out really really really fast.  Just imagine how much writing and re-writing goes on in a phone - much much more than a dash cam.  And when they do burn out? You lose all your precious data.

[Micro]

17 hours ago, Lars G said:

Question? How have you wired the dash cam into the car? Power socket or piggy back fuse?

If you are using a piggy back fuse installing the piggyback fuse (fuse tap) the wring way round can make the dash cam malfunction as you are describing. I installed one the wrong way round and it kept switching the cam on and off continually for a few seconds at a time. I turned the piggy backfuse round and it worked perfectly. 

That doesn't really make sense unless there is a poor connection inside the fuse tap. If you have the fuse tap the "wrong way" around, all that will happen is you will be "double fused" - the power will go through the bottom fuse, and then through the top fuse and out, instead of just in and through the top fuse, and out.

16 hours ago, GaryPL said:

I can confirm what you say.  This is precisely the reason why, when installing a SD card in an Android phone, you never select the option to integrate the card into the phone's storage.  Always select portable storage and make do with not being able to have as many apps. Or just pay more for a phone.

Remember most name brand SD cards have good/lifetime warranties!

[GaryPL]

10 minutes ago, Micro said:

Remember most name brand SD cards have good/lifetime warranties!

I'm going to get geeky now.

Just because a SD card has a long warranty, it doesn't mean it's going to last. Wear levelling is the technique used to preserve the life of a memory card. On something like a video camera or MP3 player, this is fairly easy to maintain. You're pretty always using different sections of the card so it wears pretty evenly.

But with a phone, if you have an app that you always run, you're going to be reading and writing to that app constantly. Every little change will be a read and write cycle.  The only way to have even wear across your SD card would be to constantly move the whole app around it.  I could be wrong, but I can't imagine phones moving apps around like this, so I just wouldn't risk it myself.

[Micro]

1 minute ago, GaryPL said:

I'm going to get geeky now.

Just because a SD card has a long warranty, it doesn't mean it's going to last.

I know, i'm just pointing out that you don't have to go out and spend more money  Some cards controllers are also smart enough towards the end of their life to go into "read only" mode (as my SanDisks did to protect the data on them.

[Lars G]

What I can say is the the Nextbase Dash Cam I installed did not like the fuse tap being round the wrong way, it kept switching on and switching off. Once the fuse tap was installed correctly the dash cam operated correctly. I can only assume that because the flow from the live travelled the wrong way it caused some voltage fluctuation which as it branched off both live to the dash cam and towards the earth. This in turn made the dash cam turn on and off. Both fuses were rated at 7.5.

If the fuse tap is installed backwards but say you have a a couple of 100W spot lamps installed which necessitates a 20amp fuse and you are draw power from the same circuit as a 1amp accessory fuse it may cause problems.

So while what you say is correct up to a point there is still a wrong way and a correct way to install a fuse tap.

In my case it did affect the installation.

[Jordan99]

Hi all, sorry for the really late reply! It was in fact the SD card at fault! 

I stupidly got a new dashcam first using the old SD card but the same problem persisted. However a new SD card sorted it right out! Now I have 2 dashcams! It’s a win win!! 

[Dee_82]

On ‎12‎/‎01‎/‎2018 at 9:45 AM, mjt said:

Well, that's just the way ordinary PC storage works and why hard drives need defragging but I expected the dashcam would be simpler.

Defragging comes form the issue of cluster sizes, if you have a 33KB file on a disk with a 32KB cluster then you end up using 2 full clusters now if that file is then spread out over multiple locations, you end up with a single file that can occupy more space than it should, in some cases significantly more. then also end up with the issue of seek times being decimated as the heads jump around the whole disc trying to read that file. which is why defragging in the old days was required. firstly to join those clusters up to free up space and secondly to put the files "together" in a physical location, more advanced defraggers would also position files in specific locations on the drive, for example large frequently accessed system files might be positioned towards the outside of the physical disc rather than bunched up towards the inner rings, why? because the outer areas of a rotating disc spin faster :)

Digital storage is a little better since cluster sizes are generally smaller than an old HDD but the key difference is there is no discernible "Seek time" so whilst an SD card behaves in almost identical manor to an HDD, it doesn't require defragging, to the same extent not only that but windows is actually pretty smart these days, especially if using NTFS and does a lot of this behind the scenes, I actually cant remember the last time I needed to do a defrag.

SSDs are even better but have the added complication of load balancing the memory so as not to kill off certain areas before others, that isn't apart of the SD card spec though which is partly why we must format our cards frequently.

in the world of computing (and dash cams) rarely is anything actually stored in a logical order, which is why my tests showed that a card with faster RANDOM access was more likely to work than a card with a faster sequential access.

this is also complicated by the fact that in some cases these blisteringly fast speeds advertised are a little naughty. Because companies have worked out that they can use the secure section of an SD card to cache data in a pre-emptive manor. This allows the card to deliver higher than normal speeds when doing predictable tasks but slower than normal when doing random stuff. 

[Dee_82]

On ‎14‎/‎01‎/‎2018 at 6:50 PM, Lars G said:

What I can say is the the Nextbase Dash Cam I installed did not like the fuse tap being round the wrong way, it kept switching on and switching off. Once the fuse tap was installed correctly the dash cam operated correctly. I can only assume that because the flow from the live travelled the wrong way it caused some voltage fluctuation which as it branched off both live to the dash cam and towards the earth. This in turn made the dash cam turn on and off. Both fuses were rated at 7.5.

If the fuse tap is installed backwards but say you have a a couple of 100W spot lamps installed which necessitates a 20amp fuse and you are draw power from the same circuit as a 1amp accessory fuse it may cause problems.

So while what you say is correct up to a point there is still a wrong way and a correct way to install a fuse tap.

In my case it did affect the installation.

Not sure about the "backwards" part, electricity doesn't have a sense of direction, it will flow from point A to point B just so long as there is a connection, but your absolutely right about which circuit you tap in to, depending on the load at the time you can get voltage droops which would potentially effect anything else tapped in to that circuit. worse still, if you did tap in a 20A circuit in to a 5A circuit then you could very well set fire to your car :/

 

[mjt]

The earliest defraggers I used, under MS-DOS, would not only defrag the files but move them in order to remove the scattered free spaces between them and collect all of them into a single block at the end. Of course this was quite a slow process and while it was going on the machine couldn't be used for anything else. As far as I'm aware the Windows defragger only defrags the files but at least works in the background whilst allowing the machine to be used for other things.

[Dee_82]

15 minutes ago, mjt said:

The earliest defraggers I used, under MS-DOS, would not only defrag the files but move them in order to remove the scattered free spaces between them and collect all of them into a single block at the end. Of course this was quite a slow process and while it was going on the machine couldn't be used for anything else. As far as I'm aware the Windows defragger only defrags the files but at least works in the background whilst allowing the machine to be used for other things.

Yup, absolutely, but not necessarily at the end of a disc, there were typically 3 zones that would be used, ideally large sequential files would be stored at the end, and smaller more randomly accessed files would be stored at the start (less physical movement of the read heads) that level of complexity wasn't added until a bit later thought, DOS, simply freed up partial used clusters then squashed everything, which in theory was good but in actuality, it was terrible, because when you started deleting stuff or changing file sizes you ended up with gaps everywhere and a requirement to move whole files just to give it more room.   windows defraggers in an online state could move almost everything in the manor you describe, but not certain system files, the big ones being the page file and later the hibernation file. but it could shift just about anything else that wasn't being used. you could tell windows to do it offline on the next reboot though.  After NTFS became popular on the desktop scene its requirement for being run was less but it could help none the less. SSDs may actually disable defragging all together because of pummelling the sectors can take can reduce the life of them.  Its actually an really interesting subject but utterly boring for anyone who isn't a full on geek! :)

 

 

[mjt]