Agreed. When I was fresh out of university, my first job had me debugging embedded firmware for a device which had both a PowerPC processor as well as an ARM coprocessor. I remember many evenings staring at disassembled instructions in objdump, as well as getting good at endian conversions. This PPC processor was in big-endian and the ARM was little-endian, which is standard for those processor families. We did briefly consider synthesizing one of them to match the other’s endianness, but this was deemed to be even more confusing haha

It never ceases to amaze me how prolific PowerPC/PowerISA was (still is?) in the embedded space

There was a ton of hairbrained theories floating around, but nobody had any definitive explanation.

Well I was new to the company and fresh out of college, so I was tasked with figuring this one out.

This checks out lol

Knowing very little about USB audio processing, but having cut my teeth in college on 8-bit 8051 processors, I knew what kind of functions tended to be slow.

I often wonder if this deep level understanding of embedded software/firmware design is still the norm in university instruction. My suspicion has been that focus moved to making use of ever-increasing SoC performance and capabilities, in the pursuit of making it Just Work™ but also proving Wirth’s Law in the process via badly optimized code.

This was an excellent read, btw.

The funny thing is that a few months ago, I bought a wand metal detector at a ham radio swap meet for $20, as a gag. Now you’re telling me that it was actually a prudent investment toward my woodworking projects??

Win!

This might be true, although I do it mostly so I can remove the earplugs and rest them around my neck if someone needs to talk to me.

The best PPE are the ones which have the fewest barriers toward using. Even the minor annoyance of having to set down untethered earplugs is best avoided, if it acts as a subconscious disincentive towards using PPE. Good safety policy adapts and accommodates this aspect of human behavior.

In a home workshop, there is no OSHA, so I’m fully responsible for my own safety.

I’m nowhere even remotely comparable to a proper furniture maker, but I can tell you some pitfalls to avoid.

Don’t cut wood without eyes, ears, and face protection. The dust, noise, or fumes will get you one day or another, if without protection. I prefer earmuffs over earplugs, but if earplugs then use the ones which tether both ends together. For a face mask, I like low-profile half-masks like this one: https://www.kleintools.com/catalog/respirators/p100-half-mask-respirator-sm

Resist the urge to dive into woodworking by starting with reclaimed wood. For example, pallets are a cheap/free source of material, but it’s a hodge-podge of different varieties, all riddled with nail holes, dents, and brown stains from rusty fasteners.

That’s not to say it can’t be done, but it certainly aggravates the process if you’re just starting. I once came across a section of 2x4 recovered from a pallet, thinking that it would cut just like the pine I was used to. Instead, it wrecked two drill bits and burned a circular saw blade as well as itself. I later mailed a sample of it to the USDA Wood Identification Public Service, who informed me that it was Acer (Hard Maple). Up until then, I didn’t even know that maple came in both varieties.

It seems hard maple is tougher than nails drill bits. I’m still learning.

If you have a particular job focus for after you’ve graduated with your CS degree, would an internship with a related company be an option? Experience with web will be of limited use for an embedded job, and embedded experience is of limited use at a quantitative analysis company.

That’s not to say the experience is entirely pointless, since many skills across the various disciplines of CS are transferable.

When it comes to what insurance does or doesn’t cover, the best answer will come from the text of the policy itself. This is, unfortunately, very dry reading and most people – although instructed to keep a copy handy – don’t have the full text nearby. That said, because of the regulated nature of insurance in the USA, standardized forms of policies exist, and homeowner policies are no exception.

The common homeowner policies are numbered HO-1 to HO-8. HO-1 only pays out only for the ten listened “perils”, and is thus the most barren policy available. Not all HO-1 policies are verbatim identical, but the gist usually matches.

We can look at this sample text from a random HO-1 (issued by American Family Insurance). Page 5 shows that “fire or lightning” is covered, so that’s a good start.

On page 6, we find the exceptions to the coverage, so if any of these apply, the policy will not pay out. Nothing in Part A would seem to apply to a DIY LED project, unless you tell me your LEDs are radioactive. Part B also doesn’t apply, unless you’re somehow perpetuating a fraud using LEDs.

Part C reads like it could apply, because it mentions “construction”, “design, workmanship or specification”, and “maintenance”, but this section only applies to the dwelling and so refers to those things which are permanently affixed to the house. That would include things like ceiling fans and light fixtures, but wouldn’t include stuff that is attached to the walls using thumbtacks or 3M Command strips. It even says that:

However, we do cover any resulting loss to property described in Coverage A - Dwelling and Dwelling Extension not excluded or excepted in this policy.

This clause basically means the exceptions on Page 6 should be interpreted narrowly, not broadly.

The point is, in the entire policy, isn’t a clause that requires listed equipment, and this is the most bare bones policy commonly available. If such a requirement did exist, then building your own PC wouldn’t be possible, since the standards bodies do not test individual computer parts – except the PSU, because that plugs into the mains.

If a fire that damages the house does occur, the most probable causes would be due to: 1) an unlisted power supply or power brick feeding the ESP32 or the LEDs, or 2) no current limiting (eg a fuse) to cut out the power supply. Other failures like a shorted LED are unlikely to actually cause a house fire, and the insurance companies and UL know this; they’re more focused on preventing arc-faults that cause an estimated 50% of electrical fires every year.

Good design and clean installation on your part, and using properly listed power supplies, will mitigate the major fire risks, leaving just software bugs and lighting snafus for you to deal with.

As a matter of completeness, if there is an unlikely fire, be it from an LED project or from a candle falling over, the insurance company will still pay. But the claim will be recorded in the CLUE database reflecting the payout amount. This often reflects negatively on homeowners, so future rate increases may occur. But that varies by state. In any case, though, the insurance policy has still done its job: cover a non-intentional loss.

I would nevertheless advise you to have a look at what sort of homeowner policy your dwelling is covered under. Everything beyond HO-1 is nicer, and some even include limited claim forgiveness of some kind (for a price).

My first thought for a compact, air-blower would be the inflater for air mattresses. They’re already fairly small, have a high flow rate, and exist in forms which accept 12 VDC.

Another option is a small tank of compressed air, but that option is either heavy (steel tank) or stores air at inefficient, low pressures (plastic tank).

I suppose a third option is to rig a can of air-duster so that it blows through the whistle. That would be mechanically simple to implement a solenoid to press the valve, although there is a small environmental cost to using cans of air-duster regularly.