There's an ARM Cortex-M4 with Bluetooth inside a Covid test kit

The Lucira test is in my opinion a bit more interesting:<p><a href="https:&#x2F;&#x2F;aseq.substack.com&#x2F;p&#x2F;inside-the-lucira-check-it-covid" rel="nofollow">https:&#x2F;&#x2F;aseq.substack.com&#x2F;p&#x2F;inside-the-lucira-check-it-covid</a><p>They include an STM32, but the instrument is performing an Isothermal PCR molecular test which makes the inclusion of a microcontroller a requirement.<p>Obviously throwing out electronics like this seems quite wasteful. But overall our society is fairly wasteful when it comes to disposable electronics.

As a European: why are there chips in this? I just broke open mine and it looks like this: <a href="https:&#x2F;&#x2F;imgur.com&#x2F;a&#x2F;muz7FIy" rel="nofollow">https:&#x2F;&#x2F;imgur.com&#x2F;a&#x2F;muz7FIy</a><p>I bought 50 of these 2 weeks ago. Were 3-4 euro a piece.

Nordic is not really that cheap if you just want a Cortex-M4. You buy Nordic parts for their radios.<p>If you just want processing power, GigaDevices has an M4 at less than $1 last I checked. Unfortunately, it wouldn&#x27;t work for the design we were working on as the standby power consumption wasn&#x27;t great.

I wonder why they didn’t use NFC. They could get away with a much simpler chip, or even a fully analog solution if they didn’t need the complexity of Bluetooth.<p>Seems like you could just about accomplish the same thing with a pair of NFC tokens, a photodiode, and some transistors. Basic components. Connect one of the two NFC chips to the coil depending on how much light is reflected off the test strip. When you scanned it with your phone the activated NFC chip would respond with a URL containing a unique ID which could be interpreted by the manufacturer.

I worked at a company that was using these chips to control doors. They&#x27;re extremely cheap chips, but writing code for them is not pleasant. Documentation is lacking and the tools people use to write code for it suck. Props to the devs who helped put this together.

Having worked on automated ELISA equipment decades ago, it&#x27;s kind of interesting to see this come full circle.<p>The earliest machines used a light source and color filter to try and get the signal from the finished enzyme sandwich. Then lateral-flow came along and it was up to a human to make the observation. Now we&#x27;re back to the computer doing it again.

US paid $230M to have this device built.<p><a href="https:&#x2F;&#x2F;www.cnbc.com&#x2F;video&#x2F;2021&#x2F;02&#x2F;01&#x2F;us-231m-deal-ellume-at-home-covid-19-test.html" rel="nofollow">https:&#x2F;&#x2F;www.cnbc.com&#x2F;video&#x2F;2021&#x2F;02&#x2F;01&#x2F;us-231m-deal-ellume-at...</a>

So my followup question is: I have a few of these, can I do anything with them once I&#x27;m done with the test? Hook up to the headers and reprogram? What about the Binax test? Or any of the other &quot;connected&quot; ones?

Note: Hackaday discussion available at <a href="https:&#x2F;&#x2F;hackaday.com&#x2F;2021&#x2F;10&#x2F;17&#x2F;electronic-covid-test-tear-down-shows-frustrating-example-of-1-time-use-waste&#x2F;" rel="nofollow">https:&#x2F;&#x2F;hackaday.com&#x2F;2021&#x2F;10&#x2F;17&#x2F;electronic-covid-test-tear-d...</a>

FYI some of those Ellume brand tests were recalled: <a href="https:&#x2F;&#x2F;www.fda.gov&#x2F;medical-devices&#x2F;medical-device-recalls&#x2F;ellume-recalls-covid-19-home-test-potential-false-positive-sars-cov-2-test-results" rel="nofollow">https:&#x2F;&#x2F;www.fda.gov&#x2F;medical-devices&#x2F;medical-device-recalls&#x2F;e...</a>

The chip is $4. The test is much more expensive than that.

Imagine a Beowulf Cluster of these!

For those interested: I ported FreeRTOS 9 to an nRF52840 in my previous job. This family used a lot. It&#x27;s in my Tado smart radiator knobs, in the AirTags.<p>I can only compare it to FreeScale chips, but one thing that pleasantly surprised me is the flexibility in pin-assignment. Instead of the pin-mux that we&#x27;d have to do on the MK24, I could just assign pins during usb&#x2F;i2c init without any limitations. The SDK is quite elaborate, although sometimes a bit difficult to use in C++.

funny there&#x27;s a chip shortage for certain chips. yet here are disposable chips...

I don&#x27;t get the worry about it being hackable. Sure, you could engineer the whole thing with crypto in mind from top to bottom. With trustzone on the chip and safetynet on the phons but what&#x27;s that gonna achieve? The test is not done in a controlled enviroment anyways. People looking to cheat the system could simply get their friends to do their &quot;hackproof&quot; tests.

I can&#x27;t believe even a fractional percentage of customers would find it useful to have wireless interaction with a disposable single-use test kit, compared to reading the result off of a passive testing strip. It would&#x27;ve been reedemable if they had sold the strips as a separate replacable product so that the electronic device could be fully utilized.

Seems like unnecessary e-waste to me.

~$30 and they werent even good &quot;Ellume Recalls COVID-19 Home Test for Potential False Positive SARS-CoV-2 Test Results&quot; <a href="https:&#x2F;&#x2F;www.fda.gov&#x2F;medical-devices&#x2F;medical-device-recalls&#x2F;ellume-recalls-covid-19-home-test-potential-false-positive-sars-cov-2-test-results" rel="nofollow">https:&#x2F;&#x2F;www.fda.gov&#x2F;medical-devices&#x2F;medical-device-recalls&#x2F;e...</a>

edit: was wrong about the test price. It should be $38.99 &#x2F; ea test.

This is cool, and I enjoy foone&#x27;s tweets about hacking around on embedded electronics you can buy at your local pharmacy. I just hope the unscrupulous don&#x27;t have a field day with the potential spin this story and headline can have.

Also see this previous HN thread:<p><a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=29637592" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=29637592</a> (Faking a Positive Covid Test (f-secure.com))

I just flew in to Minneapolis from Europe last night and they handed these out for free at the airport. Was really surprised to see the Bluetooth sign on the box.

So this is where all the chips are going during the shortage. Good to know we finally get some answers to that.

I would have understood an IoT widget for the purpose of contact tracing but for this instead? ...

Foone has specifically asked that their tweets not be submitted here.

So how long before someone starts buying up covid tests to strip these out again and resell to the supply chain challenged?

Excellent. Just what the Dr ordered.

This is depressing. Single use disposable. Full of copper, gold, tungsten, halfnium. Will leach poison into the ground. Some of the most advanced technology of our age. Use it once, toss it in the trash.<p>Meanwhile the paper versions work just fine.

Why don’t we have biodegradable chips?

.

Do we have Doom running on it?