Bitaxe is not detected when connected to a USB-C port

[rkuester]

A Bitaxe Gamma is not detected when connected to an upstream USB-C port. Presumably, this is due to lack of pull-downs on the Bitaxe's USB-C CC pins. USB Sources detect the attachment of devices through USB-C physical connections by utilizing the CC pins.

I have verified this behavior on both a modern MacBook Air and a Linux server with USB-C ports. Presumably, this would also be an issue with hubs that have USB-C ports facing downstream.

There is no issue when a Bitaxe is connected via a USB-C to USB-A cable, because USB-A ports detect attachment via devices pulling up D+ and or D- (in the Bitaxe's case, internally in the USB controller).

[MyOwn2C]

Known issue but not fixed.
Only my oldest Ultra works with USB.
All my other Supra (2x) and Gamma (3x) none of them worked with USB.
I just use UART to update if webpage update does not work.

[skot]

Uuuf, you are totally right. I'm kicking myself for removing these pulldowns a while back. I'll get these put back on in future revs. In the mean time you'll have to use a USB-C to USB-A adapter and cable 😭

I swear I had a USB-C to C cable that magically worked.

[skot]

• Connect a 5.1 kΩ resistor from CC1 to ground.
• Connect a 5.1 kΩ resistor from CC2 to ground.

[skot]

I have heard that Bitaxes work on (some) USB-C ports that are not also Thunderbolt ports.

[skot]

Confirmed adding 5.1k pulldown resistors on CC1 and CC2 on a BitaxeGamma 601 allows it to mount on my MacBook USB-C thunderbolt ports.

[skot]

The work around if you want to use a thunderbolt USB port with a Bitaxe (or you have a Mac and only have thunderbolt USB ports) is to use a USB-C to USB-A adapter.

And then use a USB-A to USB-C cable with your adapter.

And going forward I'll get this fixed on new Bitaxe HW revisions.

[NickNack67]

Couldn't we use 5.6k Ohm resistors to reduce BOM parts?