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.

Comments

Re:Maybe not the power supply?

[itzly]

Hence, even though it looks like the power supply is failing, it could simply be the power supply is turning off due to overcurrent.

No. Covering the regulator chip solves the problem. That means that it is the culprit.

Bring out the tinfoil

[thue]

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.

The new power supplies may be sensitve to EMP

[Anonymous Coward]

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

Re:The new power supplies may be sensitve to EMP

[Anonymous Coward]

Or maybe the glorious eels didn't give a shit about your puny human flash, but your device was interfering with the meter.

Re:The new power supplies may be sensitve to EMP

[wolrahnaes]

That's because you're hearing the pulsed transmission of a TDMA radio technology.

D-AMPS (AT&T pre-Cingular), iDEN (Nextel), and any GSM 2G (up to EDGE) all use/used TDMA to share the frequency, so they're all potential causes of this.

These days you won't hear it much because D-AMPS and iDEN are both dead and most GSM phones will be attempting to connect on 3G UMTS (which uses CDMA) or 4G LTE (OFDMA).

DECT cordless phones are heavily derived from GSM so it's possible that they may be able to cause the same behavior, but due to their significantly reduced range requirements the power probably isn't there. I haven't heard it from my DECT phones.

Re:Not Photosensitive

[Anonymous Coward]

A 100mW red laser pointer aimed at U16 also triggers it.
Unless you want to claim diode lasers now emit x-rays and low rise time EM pulses... it's light sensitive.
And inspecting U16 closely, it's no surprise. You're not looking at a plastic package but the laser marked underside of a bare die.

So put it in a case

[newsdee]

TFA found out precisely which chip it is (U16), covering it solves the problem.

Enough!

[Anonymous Coward]

Stop using Flash, it's a persistent vulnerability, and Youtube has an HTML5 video player now.