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by mike_d 1062 days ago
> doing that sort of thing is almost certainly a waste of time.

A waste of time for both parties, because the author is wrong.

As Wikipedia helpfully points out: "The designation C refers only to the connector's physical configuration or form factor and should not be confused with the connector's specific capabilities"

From the write up it looks like he was able to get it working with the minimum 3A required by the cable spec. You don't actually have to support C-to-C cables if you choose to not to communicate with the e-marker.
1 comments
ericswpark 1061 days ago
Hi, author here. The quote you mentioned from Wikipedia indeed says that devices don't have to implement all the capabilities of the connector. However, further down, it says the following:

> USB-C devices may optionally provide or consume bus power currents of 1.5 A and 3.0 A (at 5 V) in addition to baseline bus power provision; power sources can either advertise increased USB current through the configuration channel, or they can implement the full USB Power Delivery specification using both BMC-coded configuration line and legacy BFSK-coded VBUS line.

And further down:

> However, to connect a USB 2.0/1.1 device to a USB-C host, use of Rd[57] on the CC pins is required, as the source (host) will not supply VBUS until a connection is detected through the CC pins.

See: https://en.wikipedia.org/wiki/USB-C

As the device doesn't implement the full USB PD specs, it must advertise that it wants power through the CC (configuration channel) pins. This is part of the specifications and it must be properly implemented.

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mike_d 1061 days ago
> > However, to connect a USB 2.0/1.1 device to a USB-C host, use of Rd[57] on the CC pins is required, as the source (host) will not supply VBUS until a connection is detected through the CC pins.

Yup. You are referring to the USB 2.0 spec there, not the USB-C spec. If you follow the citation it in turn seems to be citing (not explicitly) the USB-PD spec.

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ericswpark 1061 days ago
It's a remote that charges via the USB-C port. If it doesn't follow USB 2.0 spec, or the USB-PD spec, or any spec associated with the type-C port, how is it supposed to get power from the host device/charger?
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