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I bought a £16 smartwatch just because it used USB-C

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Re: I bought a £16 smartwatch just because it used USB-C

#81

Post by xg15 »

mystifyingpoi wrote: post #76
xg15 wrote: post #70

Earlier quoted context omitted.

Would it be possible to build some kind of adapter or C-to-C cable that just contains the missing resistors? (And also probably would have to block any USB PD communication, in case you plug in any device that actually does try to use PD. So the goal would be that the charger always sees a 5V requesting device without PD support while the device always sees a "dumb" 5V charger - regardless of what capabilities the de…

Sure, just grab a C-to-A adapter and A-to-C cable. Doesn't block communication though, you could block it by using a 2-wire A-to-C cable.

OK, that's easier than I thought. And I think it should even block the PD communication as the CC line is not passed through.

Re: I bought a £16 smartwatch just because it used USB-C

#82

Post by neurostimulant »

jaian wrote: post #53
_giorgio_ wrote: post #17

Earlier quoted context omitted.

Xiaomi mi bands used to cost the same and were much better

I bought one. The touch screen was not good. The heart rate sensor was wild inaccurate at times. It was a pain to sync with my phone. And the strap gave me a rash. Not that I expect the watch in the article to be any better.

There is also huawei band, which has similar low price but with seemingly better software than the xiaomi smart band. At the very least, the sync process is easy on both android and ios.

Re: I bought a £16 smartwatch just because it used USB-C

#83

Post by michaelt »

xg15 wrote: post #69
imtringued wrote: post #58

Earlier quoted context omitted.

There is also another problem. The spec is large and it's not aimed at those who want to implement the simplest possible USB C compliant device. Based on the table of contents the most promising section is "2.3.4 USB Type-C VBUS Current Detection and Usage" but it doesn't actually talk about anything you actually need. You're supposed to click through to the section "4.6.2.1 USB Type-C Current" where it shows the ref…

Sounds like an "annotated spec" or some guides for implementers would be really useful.

When you use a well-documented chip, the datasheet will contain diagrams and they'll have a working demo board which they'll give you the full schematic for. Closer to 3 pages than 300.

Of course, a person can still get it wrong...

Re: I bought a £16 smartwatch just because it used USB-C

#84

Post by Kerbiter »

globular-toast wrote: post #57
tehlike wrote: post #54

People get surprised how cheap things really can be when they see aliexpress, and the assumption is crap. I bought a ton of stuff from aliexpress, and very rarely-if any- was crappy.

What I've learnt from BigClive on YouTube is don't buy anything that plugs into the wall. If it's low voltage then you should be fine. I'd still be wary of large lithium ion batteries, though.

I dunno mate, I've bought a very popular 60W soldering iron for like 2.5 USD. It has a ceramic heater and a knob to adjust the temperature, the default tip it came with is great, and it's also easily disassemblable. It's far better in quality than anything I could've bought locally for the same price.

Re: I bought a £16 smartwatch just because it used USB-C

#85

Post by Arech »

TBH, such a low price for so many working (!) features is an amazing achievement if not subsidized! What bothers me here, however, is...a provenance. Let me guess, it asks from your smartphone access to your location, contacts, calendar, SMS archive, email, medical records and political views and attitude towards CCP and then does some shady syncs with .cn servers "just to keep you data safe in case a meteor hits you"... Sad.

ADDED: Oh, seems like some people like to pretend that the results of "some other" companies getting this information are totally, totally the same.

Re: I bought a £16 smartwatch just because it used USB-C

#86

Post by fsflover »

squarefoot wrote: post #74
fsflover wrote: post #50

Earlier quoted context omitted.

You may like Pinetime smartwatch, which is cheap and runs free software.

I would totally support the Pine64 folks as I already did with the PineCil (really good iron btw, and I have also Wellers), but the PineTime price going from $26.99 in the US to €66.25 if bought in the EU is simply an invite to shop from Aliexpress.

AFAIK you don't have to buy it in their EU shop. You can order it from China.

Re: I bought a £16 smartwatch just because it used USB-C

#87

Post by denysvitali »

KORraN wrote: post #37
incone123 wrote: post #25

I have a Garmin with a monochrome LCD face. Ok, it can't compete on price but battery life is a couple of weeks (and can top up with solar) so the proprietary cable is not a big problem.

I was also a happy Garmin Instinct Solar user. It is until after two years it started to turn off whenever it vibrates. I disabled vibrations, but it's reduced to an expensive step counter now.

Seems like a battery issue. Probably the vibration draws too much current and the battery just drops its voltage. Have you tried changing the battery?

Re: I bought a £16 smartwatch just because it used USB-C

#88

Post by jadamson »

DoctorOetker wrote: post #75
snops wrote: post #62

Earlier quoted context omitted.

It can, it just needs the two resistors, which is the cheapest possible thing the standards committee could have asked manufacturers to do. USB-C gets complicated at the high end, but for basic functionality I think the standards committee did a very good job at making the cheapest way to do it the correct way, e.g. a USB-C to 3.5mm audio adaptor can be entirely passive, it just needs the right resistor in it.

>e.g. a USB-C to 3.5mm audio adaptor can be entirely passive, it just needs the right resistor in it. How does that work? is each USB-C host port, or downstream USB-C hub port required to contain a stereo DAC? Does the standard impose performance requirements like dynamic range, noise, minimum sample rate,...? Does it also mandate the jack can be used for mic / line-in? Does it similarily stipulate inclusion of an AD…

It doesn't mandate any of that, it's an optional feature.

The data pins are repurposed for analog audio, so it won't work with hubs. You'd of course need a DAC for output and an ADC for mic input, but the point is to replace a headset jack, so you'd have those already.

https://www.usb.org/sites/default/files/USB%20Type-C%20Spec%... (PDF, page 309)

Re: I bought a £16 smartwatch just because it used USB-C

#89

Post by rvnx »

Arech wrote: post #85

TBH, such a low price for so many working (!) features is an amazing achievement if not subsidized! What bothers me here, however, is...a provenance. Let me guess, it asks from your smartphone access to your location, contacts, calendar, SMS archive, email, medical records and political views and attitude towards CCP and then does some shady syncs with .cn servers "just to keep you data safe in case a meteor hits you…

Sounds like any Samsung or Google watch

Re: I bought a £16 smartwatch just because it used USB-C

#90

Post by andrepd »

Arech wrote: post #85

TBH, such a low price for so many working (!) features is an amazing achievement if not subsidized! What bothers me here, however, is...a provenance. Let me guess, it asks from your smartphone access to your location, contacts, calendar, SMS archive, email, medical records and political views and attitude towards CCP and then does some shady syncs with .cn servers "just to keep you data safe in case a meteor hits you…

Implying all US electronics don't ask from your smartphone access to your location, contacts, calendar, SMS archive, email, medical records and political views and attitude towards the US and Israel and then does some shady syncs with .com servers "just to keep you data safe in case a meteor hits you"... x)
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