A USB-A to USB-C cable is required because the QuickLogic thing+ USB Type C connector is not implemented correctly

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nimish
Posts: 4
Joined: Mon Jun 19, 2023 10:03 pm

Hi, when debugging why a USB-C to USB-C cable wouldn't even get power on a MacBook Pro port, I stumbled across the schematics for the QuickLogic thing+

Unfortunately the USB-C implementation is 100% out of spec -- it doesn't connect the CC1/CC2 pins to anything (!) when it needs to connect them to ground via a 5.1k termination resistor.

https://github.com/sparkfun/QuickLogic_ ... ematic.pdf Take a look at the USB-C connector: the CC pins are simply left floating. Without them the host won't even know there's anything on the line and doesn't allow any power.
Ruthlehm
Posts: 1
Joined: Wed Apr 08, 2026 7:57 am

Wow, that sounds frustrating! Have you ever encountered something similar where a device completely disregarded a standard? I once had a USB drive that claimed to be 3.0 but consistently performed at 2.0 speeds, no matter what I tried. It was definitely a lesson in trusting, but verifying. Makes you wonder what other corners are being cut, like when Freddy Fazbear is "just" malfunctioning.
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