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If you have kids they play with turning the light switch on and off. So I can see the need not to reset by accident.

A simpler solution is to have ordinary plain light bulbs. Probably friendlier to the environment due to less electronics. It’s hard to hack ordinary light bulbs so they are secure.

Reset button makes sense though. Reset button are costlier for bill of materials so manufacturers save on that.




Reset button is actually a safety issue, as the bulb would have to be plugged into the mains to register the reset. A metal paperclip inserted into the body of the light bulb would be very problematic from an electrical isolation point of view.

The big failure arguably is not testing the firmware sufficiently (or building in recovery algorithms) to necessitate a reset procedure in the first place.


Lightbulbs don’t get handled in operation. So you can have a huge reset button and no need for a paperclip.

As to firmware, cosmic rays for example randomly flip bits. Which means for any large scale deployments you want a reset option.


Let me think - the reset button can only work when the light is powered up (and maybe too hot to touch) - you can't mount it on the metal base because that's live when it's on, and so the light fitting is designed so you can't touch the base. you could mount it in the glass but it would cast a shadow ...

any solution has to cost less than a penny ...


> Let me think - the reset button can only work when the light is powered up (and maybe too hot to touch)

A capacitor that is kept charged during normal operation, and that powers the reset circuit which you close with your metal pin once you unscrew the bulb. The circuit flips some bits in persistent memory of the bulb.


So it resets every time you leave the bulb off long enough for the capacitor to discharge?


No. "Reset" is done by a circuit, and the only way to power it is by connecting that capacitor to it by pushing something into the reset pinhole. If you don't do that, capacitor eventually discharges but since the circuit never gets powered, no reset happens. So after a while you need to connect the bulb to mains power in order to be able to perform reset.


Most LED’s have a wide bit between the electric bit and the glass. Having that live would be a significant safety risk which I doubt major companies would risk. https://www.homedepot.com/p/Philips-75-Watt-Equivalent-A19-N...

It’s a heat sink that gets hot to to the touch, though not that quickly as your talking ~10w of waste heat. Sill several ways to do a reset switch just after power is off.


Firmware is likely to be stored in flash memory, which is far more resilient to cosmic rays than SRAM or DRAM. You might find a bitflip is so unlikely it's far below the other in-service failure rates and you'd rather just handle the returns. Of course, a reset is still useful for other reasons. All assuming you don't use the bulbs in your airplane/space shuttle!

Edit: a source https://www.researchgate.net/publication/4082030_Flash_memor...


And what happens when you lose your phone and need to pair it with a new device?


It has an app, right? So why not allow factory resetting from there?


Sure, but the whole point of factory reset is when the paired phone app no longer talks to the bulb. ( You might have lost the phone or the account details). It just allows you to start with the assumption you are physically in control of the bulb and hence are authorised to reset it.


Because often you want to reset to defaults when there is an issue connecting to the app.


So if you have this installed in a ceiling fixture, you have to get a ladder, take off the shade, hope the bulb happens to be oriented the right way in the light fixture for you to access the switch.

Or, you could play that video and follow along and flip a switch a few times.

Which one sounds like a better UX?


> If you have kids they play with turning the light switch on and off. So I can see the need not to reset by accident.

These are "smart" light bulbs, so I am guessing you are not supposed to control them by cutting of their power with a physical switch.


Temporary battery only used when disconnected from power, like alarm clocks etc




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