Add a USB-C Female socket to NanoPi Neo

Question

I'm working on a project which enables two USB ports on the NanoPi Neo core board.

NanoPi Neo Core pinout

One is a USB Type-A Female, to connect devices with a regular USB cable, and the other one should be USB Type-C Female, to use a USB Type-C Male-Male cable to connect devices, NanoPi will act as a Host where we will connect devices.

USB Type-A is easy to connect and it's working ok, but USB Type-C Female only provides power, no connection is stablished.

This answer refers to the USB Standard, which points to pull-down with a 5.1k resistor A5 (CC1) pin, which doesn't work, but, in the correct answer, it states to be a USB-C to USB-A conversion diagram, which is not our goal. Anyway, it didn't work.

This guide, in section Converting USB 2.0 Device and Host SoCs to USB Type-C, adds two pull-down 5.1k resistors to both CC pins and that's it, no other changes, but no "connection" to the device.

This question, which points to the previous link, includes a diagram which illustrates both CC pins to be pulled-down to just replace the connector.

And for the final one, this link bears out the correct wiring I'm using:

• USB-C GND1 + USB-C GND2 -> NanoPi GND
• USB-C VBUS1 + USB-C VBUS2 -> NanoPi 5vOUT
• USB-C B6 + A6 -> NanoPi USB2_D+
• USB-C B7 + A7 -> NanoPi USB2_D-
• USB-C A5 -> 51k Pulled-Down
• USB-C B5 -> 51k Pulled-Down

This should be the right diagram, but for any reason it's not working. I'm I missing something? I'm I using the right diagram? Is this, use a USB-C Female instead of a USB-A 2.0 Female, doable?

Answer 1

The 5k1 pull-downs are used for USB devices, not USB hosts which is what you want to make. Also your schematic has 51k pull-downs which are of course incorrect value for any purpose.

So the first problem is, you need to be Type-C host so you need pull-ups.

But that still is not the correct way to make a Type-C receptacle. If you have a receptacle, you are not allowed to output 5V directly. You must have the VBus disconnected, and only when you detect that there is a device connected, you are allowed to enable the 5V to receptacle.

If you had a Type-C plug then it would be allowed.

It might be best to just put two Type-A receptacles and use standard cables with Type-A plug and Type-C plug.