I think eben sets the correct level with stick blutac on itjoan wrote:I skimmed the thread. Apologies if this has already been posted a dozen times.
OK, so where's your simple experiment, where's your empirical evidence? Where's the details of how I can repeat your tests and prove or disprove them?simpex wrote:
I believe that a lot o light sources, that people use at home or in labs, can reset Raspberry Pi 2 if they are positioned less than 20 cm away from the board.
The warning in today's blog post was for this very reason...shaz wrote:I think I corrupted my SD card as it rebooted when taking a picture.
Now I cannot read the SD card from my laptop and the ACT light on the Pi 2.0 remains stable instead of blinking, without any video appearing / booting.
Is there anything I can do?
Laser's should by definition not diverge at al. So they should have the same intensity across the entire dot. However, LED lasers are a bit rubbish and will have an intensity change, but not a huge effect and the dot is so small, that the speed of the passing should make very little difference. You would also need to be moving the dot extremely accurately and extremely slowly (more accurately and slowly than you could hold the laser)simpex wrote:Speed is relevant because the laser dot does not present a constant intensity across its entire surface. The edges of the spot have close to zero intensities while the center reaches the maximum. As the red dot comes closer to the IC that causes the glitch, more and more light illuminates the circuit. So, that U16 (I hope U16 is the real culprit) is gradually illuminated by the laser dot.jamesh wrote:Speed of moving the dot is irrelevant - the point is that as the dot hits the edge, there is an instant increase in light (providing it's a decent laser). One moment unlit, next moment lit.
What exactly do you see on the oscilloscope when a laser dot is switched on, pointed a few inches away from U16 and then moved above U16?
Luckily, I do not have a Raspberry Pi 2 so I can just ask somebody who already bought one, it could be the topic opener, Peter O., to illuminate his board with a halogen lamp and see what happens.clive wrote:You might want to test your data-surmised hypothesis. By shining one of those lights on a Pi 2 for examplesimpex wrote:Raspberry Pi 2 can easily come close to a halogen lamp (http://www.homedepot.ca/catalog/halogen-bulbs/172459) that likely will cause it to either freeze or reset...
I just felt some people were on the border of concern trolling!rahlquist wrote:You make valid points but I believe everyone is just trying to make sure its figured out and everyone wants to contribute. A case may fix 99% of issues but most of us like better than 99% reliability if we can manage it I am sure. In my case the primary use for some of my Pi is in part as IP cameras. Some of the cameras do face roadways and I need to know that some person with 2M candlepower Xenon headlamps, light bars, whatever is not going to catch my Pi and poke it in the eye on the way by.Lob0426 wrote:How many of us are going to be taking pictures, shining Lasers or any other bright source, on operating RasPii, now that we know there could be an issue? I am putting mine into a case.
So, yes, for a lot of us who dwell in an evil lair, poorly lit, with no bright corona or xenon or laser discharge it's a non starter of an issue For others we just want to understand and fix, to prevent the 1% random error from this item.
That bit in the blogpost where we were talking about wavelengths and intensity? Lightning is definitely not going to trigger this event.g7ruh wrote:Nobody has mentioned thunderstorms (I think). Lightning is rather bright and I suspect will trigger this event. We shall see if we get reports of sulking pi after a thunderstorm. Bit hard to test in the UK in winter.
We have one in the office. Nothing happens. Really - PLEASE read the blog post I wrote today; this is all covered there.simpex wrote:Luckily, I do not have a Raspberry Pi 2 so I can just ask somebody who already bought one, it could be the topic opener, Peter O., to illuminate his board with a halogen lamp and see what happens.clive wrote:You might want to test your data-surmised hypothesis. By shining one of those lights on a Pi 2 for examplesimpex wrote:Raspberry Pi 2 can easily come close to a halogen lamp (http://www.homedepot.ca/catalog/halogen-bulbs/172459) that likely will cause it to either freeze or reset...