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Xenon Flashes Can Make New Raspberry Pi 2 Freeze and Reboot
An anonymous reader writes Unfortunately for Raspberry Pi 2 owners who are trying to photograph their devices, ... the Raspberry Pi 2 has been found to be Xenon flash sensitive. Any camera with a Xenon flash aimed at the device is causing the device to freeze for a few seconds before rebooting. The forum thread about the bug is an interesting play-by-play of how the problem was narrowed down.
Cool. The linear reg on the previous models worked perfectly, but was rather less than ideally efficient - 5V power in, but almost all the power consumed goes via the 3.3V rail.
Reports are saying the power supply is causing this fault.
That might not be the case. Bright UV light will create electron hole pairs in the gate of transistors turning them all *on*, which will cause the chip to use much much more power since push pull output stages of logic gates will now be shorting the power supply.
Hence, even though it looks like the power supply is failing, it could simply be the power supply is turning off due to overcurrent.
An datz da fax Jax!
I gotz Intelz up insidez me!
Mr Slave
Intel inside.
It seems the Pi2 is not photosensitive, but x-ray sensitive, or sensitive to electric fields, the xenon flash is a high voltage discharge that both generates some high energy photons and sends a electromagnetic pulse through the ether. Early radios where spark gaps. If light can not penetrate (inside the voltage regulator) it can't affect the component.
I am guessing that wrapping it in tinfoil would fix it? I know it works great for stopping the mind-control waves from getting into my head.
They should have used Silverlight instead of Flash.
Years ago when I visited an aquarium I encountered a very strange situation
I was in front of a tank which has 3 electric eels, and in front of the tank there was a 'meter' measuring the power the electric eels were discharging
So I took out my camera (real camera, with powerful Xenon flash light module attached)
Before I pressed the button the Xenon flash was charging (as I said, powerful flash light) and all of a sudden the 'electric meter' in front of the tank indicated that there was an electric discharge from the electric eels
At first I thought it was a coincidence. Then I wanted to take another picture. Again, my Xenon flash light module was charging, and again, there was a jump in the 'electric meter' reading. This second time around I started to suspect that there was a connection in between my Xenon flash light module and the electric eels
The third time around I only use the Xenon flash module. Again I hold it close to the tank, and charge it, and again, the 'electric meter' got another 'shock'. I repeated the experiment the fourth time, fifth time, .... every single time while my Xenon flash module was charging up,. the electric eels inside the tank somehow 'felt' something and gave an electric discharge
I never know the exact reason. My suspicion is that there might be some EMP effect, some wave or some magnetic field, or something like that
What I described happened years ago. I never get the chance to test out my theory
Perhaps someone can test if Xenon flash emits EMP, or not
That means I can't play Space Quest and Leisure Suit Larry at the same time.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
He only mentions that it crashes, everybody else answers the question yet he now goes by "Discoverer of the PI2 XENON DEATH FLASH !"
Parent is 1) full of shit and 2) likely a negro or other undesirable.
The same people are photographing their food. And yet, this is the "Maker Movement", touted as the new industrial revolution. Truly, we are doomed.
It is an illustration of how assembly-line our intelligence has become that we can produce such technological marvels as a Raspberry Pi - a science fiction fantasy just decades ago - but talented engineering teams forget to do something like put packaging on the chip die.
I took a picture of my Raspberry Pi 2, you'll never believe what happened next!
... or simply an RF issue with the huge capacitor discharge which is a feature of Xenon flashguns.
Inquiring minds want to know the mechanism...
TFA found out precisely which chip it is (U16), covering it solves the problem.
The ENIAC Demo Competition
He is clearly overplaying it so probably just joking. :)
Stop using Flash, it's a persistent vulnerability, and Youtube has an HTML5 video player now.
Hopefully this doesn't mean more problems in noisy environments
as was hopping to test the PI2 to run an Industrial CNC motion controller.
Really not surprising. The pi2 is pretty crappy hardware. So many better micro computers for projects, not sure why 'geeks' obsess over it.
a de facto EMP / light sensitivity torture test!
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
ymmd
There's plenty of cases of electronics misbehaving due to exposure to strong light. Glass enveloped diodes (such as signal diodes) can be notorious for it, as can the black plastic encased units if the light is strong enough.
Small bare CoG (Chip on Glass) LCD panels will crash / hang when you use the flash on the camera taking photos of them in operation ( same reason, the controller die is exposed ).
It's not EM-pulse or xrays causing the problem, just good ole silicon junctions being exposed to intense light :)
No, I don't think so... Looking for his 15 minutes more likely.
Military hardware for specific applications is tested for light sensitivity, but it is not a common test.
I have never seen any industrial control equipment subjected to such a test.
Betcha there's gpnna be a whole lot of "unofficial" testing done starting Monday morning, I'll betcha.
Xenon was the development codename for the Xbox 360 video game console. I was more like: Since when did Adobe port Flash Player to the version of Internet Explorer on Xbox 360? Was it Wii-nus envy to catch up with Nintendo's "Internet Channel powered by Opera"?
Industrial electronics need to be tested to prevent the circuit from picking up radio signals. Usuall this is prevented by a circular line around the edge of the board. This also happens to be the route of the power supply in some cases, so maybe the +5/ground circuits are functioning as antennas, and it is not the component that is sensitive..
"Nothing like this will be built again"
I've just had a really amazing experience: a guided tour of the nuclear reactor complex at Torness on the Scottish coast. ... Cameras were verboten -- not because of security, but as an operational precaution. For starters, some embedded controllers in racks in the auxilliary deisel generator control rooms have EPROMs which have been known to be erased by camera flashes in the past, triggering a generator trip ...."
http://www.antipope.org/charli...
Good thing people aren't arbitrarily writing judgmental posts about YOU because of your screenname. Imagine if EVERYONE chose to waste their day in such a fashion.
I've seen it before back in the day. They are not very efficient but they could cause a critical spike if they are not isolated from a bus.
Well, he did discover it, right? He isn't going by "SOLVER of the PI2 XENON DEATH FLASH", now, is he?
The device at U16 on Raspberry Pi 2 v1.1 appears to be an ON Semiconductor NCP6343 DC converter provided in a WLCSP-15 package.
Like all CSP packages, the bare die is photosensitive and needs to be protected from incident light if fault-free operation is expected. Usually such devices are embedded in closed cases like cellphones which prevent light ingress.
However, if the normal operating environment includes uncased bare boards or transparent cases (which are both common and normal for Raspberry Pi), then it is imperative that CSP-packaged dies be protected from light by other means such as opaque epoxies or caps, otherwise such devices cannot be expected to operate within specification.
It is a normal part of the engineer's job to understand their product's operating environment and the components they use, and to design accordingly.
and the RasPi 2 already has a Flash vulnerability
As first to coin the phrase "xenon death flash" (and do the blutack fix) :)
it was funny watching the story spread with the phrase intact
I'm sure someone has already mentioned this (and I tried posting on the RPi forum but it's having a 'senior' moment)
This is likely just RF overload.
Stick some foil over the RAM and CPU (and voltage reg) and see if things improve - you mentioned flipping the board over so I would imagine that RF (Radio Frequency) is the culprit (as the xenon flash is basically a wideband (all frequencies) radio transmitter). That close is probably going to couple with some squiggly bit of the silicon and do 'interesting things'
Very interested to see if the foil improves things (alu tape would be a good start)!
Regards
piemmm
I am blushing and filing this with "gullible is not in the dictionary".
.....
razn1 ~ $ w
23:14:15 up 11 min, 1 user, load average: 0.00, 0.04, 0.05
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
bob pts/0 whitechrome.wr.t 23:14 7.00s 1.29s 0.04s w
razn1 ~ $
razn1 ~ $
razn1 ~ $ # flash flash flash... must be one honking flash but mine is big.
razn1 ~ $
@razn1 ~ $ w
23:16:14 up 13 min, 1 user, load average: 0.02, 0.04, 0.05
Truth is stranger than fiction, but it is because Fiction is obliged to stick to possibilities; Truth isn't. Mark Twain.
I was working to my thesis in nuclear physics, and I was developing a new analytical method based on beam-induced radiation spectrometry. In one of the beam lines we had an alpha particle detector (basically a large Si crystal with a gold-plated surface) that was driving me crazy. When we used the detector for measurements it worked perfectly, but when we turned the beam off and I entered the radiation facility to do some measurements, it was insanely noisy and could not be properly calibrated. I was staring at the screen of the scope looking at the huge noise floor and scratching my head, when at once the noise disappeared, then came back again. This repeated for a few times and suddendly I realized what was happening. The vacuum chamber where the detector was installed had a glass window hidden to my sight that was sometimes used for remote inspection with a TV camera. A technician was doing some maintenance work, walking back and forth in front of the window. When he was close to it the noise disappeared, and when the window glass was clear of obstacles the photoelectric effect in the detector caused the noise! During irradiation tests nobody was inside the facility, so we turned off the lights, and this explained why the detector worked without problems. A piece of duct tape on the glass window fixed the problem for ever, as always...
This is a simply a case of poor hardware design. The design engineer should have known that exposed silicon is sensitive to light (Remember the glass window EPROMS) and used a packaged version of the regulator.
I must be old. It took me several minutes to realize that neither the title nor the summary for this article were talking about Flash animations that were made by an Internet user who went by the name of Xenon. (His animations were famous-ish on 4Chan for containing copious amounts of ear-rape, among other things.)
It's the "EMP pulse" of triggering the xenon strobe. Nothing you can do by harden the rPi2 to transient. If' it's this sensitive, you probably don't want to take it to some super drive place like New Mexico either because static discharges are a "way of life" and will likely do the same thing.
Xenon makes a nice flash because it's so white. And it's so white because its emission spectra is so wide, going well into the UV. Some lamps filter the UV out, some don't; there's not enough light in a typical photographic flash for the UV to have any impact. But UV photons are important for upsetting electronics because they have enough energy to pop electrons out of potential wells in silicon/silicon-oxide IC circuits. Visible and IR photons generally don't. Remember the 2708 series of NVROM memories? They had a transparent window that let you erase them with a UV lamp (and a long wait); regular visible light had no effect on them. The visible photons, for any practical flux, just didn't have enough energy.
Well stop taking pictures of live electronics with the cover off. Dumbasses. It's hardly going to affect its everyday operation is it?
Wondering how your neighbor got your banking info? Well, you transmitted it to him...
--- Keep the choice with the user..
Most IC chips are very sensitive to UV light, thats why the plastic cases are usually black to stop the light.
Every now and then, a manufacturer has some personell who don't know that, and they choose the wrong material for the case.
Usually can fix it by covering with something opaque. Tinfoil works good, as long as you don't short out anything.