We have confirmed the death flash phenomenon where Raspberry Pi 5 is forced to shut down when exposed to strong light, so we would like to share the details.

The verification equipment for the single board computer 'Raspberry Pi 5' arrived at the GIGAZINE editorial department, so I was trying various things to create a review article, and when I irradiated a specific part of the Raspberry Pi 5 with strong light, it was forcibly terminated. has been confirmed. I have collected as much information as possible about the conditions that cause forced termination and the logs of forced termination, so I have summarized the details.

Raspberry Pi 5 – Raspberry Pi


◆About technical aptitude
The Raspberry Pi 5 that arrived from the Raspberry Pi Foundation to the GIGAZINE editorial department has not received technical standards compliance certification. Therefore, before using the Raspberry Pi 5, we have submitted a notification under the ` `Special System for Experiments Using Equipment Not Obtained Technical Compliance .''

◆How we confirmed the phenomenon of forced termination when exposed to strong light
A sample of Raspberry Pi 5 has arrived from the Raspberry Pi Foundation.

Inside the box was a Raspberry Pi 5 and instructions.

When I checked the instructions, it says, 'Do not expose the board to high-intensity light sources (such as xenon flash or lasers).' In past models of Raspberry Pi,

a death flash phenomenon in which the system stopped when exposed to strong light was confirmed, but I was wondering if the same phenomenon would occur with Raspberry Pi 5, so I was wondering if it actually happened. I decided to try it.

The verification method is simple, irradiating the Raspberry Pi 5 with a camera flash from all directions. The flash used for verification is the built-in flash of the DMC-GH4 .

As a result of actually irradiating the Raspberry Pi 5 with a flash, it turned out that if the flash was irradiated on the back of the Raspberry Pi 5, the system would shut down. When you play the movie below, you can see how the system crashes and restarts the moment you shine a flash on the back of Raspberry Pi 5.

Death flash phenomenon occurs when the back of Raspberry Pi 5 is illuminated with strong light - YouTube

On the other hand, the surface of Raspberry Pi 5 did not terminate the system no matter what angle the flash was irradiated with.

If I shine strong light on the back of Raspberry Pi 5, it will force shut down, but the front side seems to be fine - YouTube

I was curious about what kind of processing is being done when the system shuts down, so I connected the USB-Serial Conversion Kit ' USB-UART232RM ' to the Raspberry Pi 5 and tried to obtain a log of flash irradiation.

First, below is the log when restarting using the normal procedure. The system is starting up after the shutdown process has been performed.

Below is the log when irradiating the flash. The system is starting up without any shutdown processing occurring. In other words, if you irradiate the Raspberry Pi 5 with a flash, it seems that the normal shutdown process will not be executed and it will be forced to shut down.

◆Search for conditions for forced termination
I found out that irradiating the Raspberry Pi 5 with a flash causes it to forcefully terminate, so I decided to investigate the conditions that cause it to forcefully terminate. It is assumed that the effect of flash on the system is due to electromagnetic waves and photoelectric effects, so first, in order to confirm whether the effect is due to electromagnetic waves, we prepared cardboard as a ``material that allows electromagnetic waves to pass through but not light.''

When I placed a cardboard over the Raspberry Pi 5 and used the flash, no forced shutdown occurred. From this, it seems likely that electromagnetic waves do not affect the forced termination.

Next, we prepared aluminum foil as a ``material that does not allow light to pass through'' and applied tape to the surface to insulate it.

Cover the Raspberry Pi 5 with a piece of aluminum foil taped to it and irradiate the flash while moving it little by little to find the parts affected by the flash.

As a result of searching for areas affected by the flash, we found that a forced shutdown occurs when the flash is applied near the power supply USB-C port and HDMI port on the back.

It looks like this when the part where forced termination occurs when the flash is irradiated is surrounded by a red frame.

Forced termination occurred even when the HDMI cable was unplugged.

Up to this point, I had verified using the Raspberry Pi 5's genuine power adapter '

Raspberry Pi 27W USB-C Power Supply ', so I changed the power adapter to ' APD-V140AC2-BK ' and verified it. A forced termination occurred as well. This indicates that the problem is not specific to the power adapter.

In addition, since only one Raspberry Pi 5 was used in this verification, there remains the possibility that the phenomenon of forced termination when irradiating the flash is a problem unique to the sample sent to the GIGAZINE editorial department. Masu.

◆Forum now open
GIGAZINE's official Discord server has a forum related to Raspberry Pi 5. Anyone can write from the link below, so please write something like 'I'm curious about ○○'.

• Discord | 'Raspberry Pi 5 has arrived at the GIGAZINE editorial department, so I'm going to review it, but what do you want to know? ' | GIGAZINE

in Review,   Hardware,   Video, Posted by log1o_hf