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Comment by sgt | Hacker News Reader

It's pretty crazy that a lamp, even though it's a smart lamp, must have such a powerful processor.

This gets said all the time, but what do people expect? Chips that can run doom are basically the bottom tier chip now. There is no point making lower power chips because they would use the same physical resources to produce.

Do you find it odd that most people buy chairs capable of supporting 200kg when they know that no one over 100kg will ever sit on it?

The latter is overengineering for safety, using a fast chip isn't. But I imagine it's the cheapest, small SoC that offers bluetooth or wifi, or whatever a "smart" lamp needs. If someone wants to rail against the need for smart lamps, however, they'd have a point.

Ikea uses zigbee. Better for this purpose than wifi or BT (but sadly not much).

A Cortex-M33 microcontroller costs like a coffee, and much less that that for Ikea that can then sell more lamps and at a higher margin, because people like introducing more complications in their lives, like software updates for what used to be a wire and a switch.

> Do you find it odd that most people buy chairs capable of supporting 200kg when they know that no one over 100kg will ever sit on it?

it solved through more materials or technologies per $ input. Chairs that can support more mass require non-trivial production and/or rare materials. You likely can produce a chair out of titanium or carbon fabric that could support more weight. There're no chairs that are both cheap and can support variety of use cases.

>Do you find it odd that most people buy chairs capable of supporting 200kg when they know that no one over 100kg will ever sit on it?

I guess you never had sex on a chair.

or partner/kids sitting on top of you

That is not really accurate. There are plenty of chips being made that are less powerful. Such as the Epson S1C60 which is a 4-bit MCU capable of running at a whopping 1MHz frequency

Is it materially cheaper? Pennies per device isn’t going to be particularly compelling in this application, if it even is cheaper to begin with.

Also at too low power, it might not be able to perform the “smart” aspects of the light

Chairs are given large safety margins, and designed to accommodate a wide range of people. Chips also have safety margins, but chips are not chairs, and there are other forces causing overpowered ARMs to be put into simple electronics, namely prevalence and mass production bringing the price down to pennies, so much so that it costs far less to develop some high level code for an cheap overpowered ARM chip than develop some more specialised embedded code for more "appropriately" sized microcontroller for the job. Sometimes things will still sway back to the specialised chips when things like power constraints or more specific hardware features carry enough weight for the purpose.

Perhaps the cost of programming the smaller chips is high enough to offset it

It could be that they just use the same processor for multiple products even if it is overpowered to be able to reduce cost in acquiry, hardware design and software development.

Still crazy for a mass product.

It's not particlarly powerful by modern standards. The processor in question is an ARM Cortex M33, which is available with single or dual 32-bit cores, at clock speeds of 150 to 240 MHz. But when Doom was first released, a typical PC would only have run at 66 MHz.

You might not need that kind of processing power continuously, but consider that the lamp has to connect to WiFi securely, then talk to your smart home HUB securely, meaning setting up TLS connections, and you want it to respond to commands in much less than a second, you want that kind of processing power in bursts.

We do not need a processor this powerful to do this at all. Garage door openers have been around for ages and the only novel thing here is the strength of the encryption, which could be done in hardware.

It's simply that this is "easy" because these chips are plentiful and cheap enough.

The stories of Russia harvesting chips from washing machines and dryers to put into munitions systems[1][2] demonstrates just how much "excess" there is in terms of compute power in the average smart device.

[1]: https://www.techspot.com/news/94589-russian-tanks-using-chip...

[2]: https://www.appropriations.senate.gov/hearings/a-review-of-t...

This particular one doesn't do WiFi, just ZigBee...they have a separate bridge box for that.

It is a fairly pricey choice for what it's doing...$5-6 per piece for single unit purchases.

It's even more crazy to realize back in the days we were able to make entire games that could run on hardware like this.

...and then use the same hardware for office tasks.

...and were amazed we could do any of it at all.

You're right. Kids today have it easy. They can just go and pick a cheap 64 bit ARM cpu off the shelf and call it a day. We had no such luxuries!

You want your "smart" lamp to respond quickly to reduce power consumption and air time. Just a short sprint once is a while instead of a slower 8 bit cpu crunching on algorithms designed around 32 bit operations. The wider ALU and registers are cheap. The fetch and decode logic is almost identical in area and uses less power because you can implement your application executing fewer instructions. Have a look at the code size produced by common C compilers for something like AES128 targeting a Cortex M0+ (or M33 in this case) and a ATmega. You'll see lots of short helper functions that depending on compiler settings are either called very often, inlined or even inlined and unrolled.

And yet i purchased a number of LEDs with mr16 gu5.3 bulbs just like the photo from TFA, and none of them work well in the minimum dimmer settings, they're all way too bright.

Maybe I've got it all wrong and i should have played doom on them instead.

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