On Wed, Sep 23, 2020 at 11:36:39AM -0400, Russell Reiter via talk wrote:
I've made some progress and then lost it again. I had to take a high def photo of the writing on the cable to read that the cable is rated 3.0 and my mb is only rated 3.0 but the peripheral card is usb 3.1. I think this is why the mb connection hangs the system on usb 3.0, but the peripheral 3.1 card does not. I'm not sure which iteration of usb provides "alternative" bus capabilities, ie. video and up to 100w power.
USB 3 naming is crazy. My understanding is: USB 3.0 = USB 3.1 Gen 1 = USB 3.2 Gen 1x1 = 5Gbps USB 3.1 Gen 2 = USB 3.2 Gen 2x1 = 10Gbps USB 3.2 Gen 1x2 = 10Gbps (requires USB-C) USB 3.2 Gen 2x2 = 20Gbps (requires USB-C) So a USB 3.0 port is also a USB 3.1 Gen 1 and a USB 3.2 Gen 1x1 port. Confusing enough? As for power, USB-PD (power delivery) allows USB-C to provide 2A at 5V or up to 3A or 5A at 12V and 20V, for a maximum of 100W. They start at standard USB 5V, then negotiate what each end supports and if in agreement, switch the voltage and current. -- Len Sorensen