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Comment by nimish | Hacker News Reader

More like $60, or charger lab has a nicer one for about the same price. https://estore.st.com/en/products/evaluation-tools/product-e...

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> charger lab has a nicer one

Power-Z KM003C? https://www.amazon.com/ChargerLAB-KM003C-Portable-Charging-V...

Yes, I have a few of these and I love them

The big question is how it performs with high-speed data. Google's Twinkie and this Twonkie clone use a design which messes with the data lines as little as possible so they'll probably still work with USB4 if you're lucky, but the linked ST device is routing those traces all over the board. No issue with USB2, might work with 10Gbps USB3, but anything more? I wouldn't want to bet on it.

ChargerLab's KM003C passes in Thunderbolt 4 correctly at least.

(source: I have one and can have it between my macbook pro and a TB4 dock and two displays work correctly)

Nicer in what way? I've used the one referenced in the first comment (CY4500) and it worked quite well. I'm not entirely sure what could be done better.

Nice to know that cheaper ones exist though - is the supporting SW any good (reading out packets, recording etc)

Nicer in that it has a good HMI. Anandtech has a nice review: https://www.anandtech.com/show/18944/usbc-power-metering-wit...

This isn't quite the same thing, I think. The Cypress one has decent software for reading individual PD packets and debugging PD/TCPM implementations.

Even if you can read out the packets with that, it doesn't look like it has a good pre-existing analysis software for it, which is a large part of the value proposition for the cypress version.

That's what sigrok or wireshark are for, IMO. Of course, you lose something for half the price. The ST one does have a protocol analyzer.

Well, you can't read PD packets at that layer - they are only realistically visible at the driver layer and below, as the TCPM driver will manage the PD negotiation (and the main benefit of these analysers, at least for me, was to help write such a driver in the first place :))

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