Connecting Enigma touch to mobile phone.

[Bart Wessel]

I noticed that when I connected the Enigma touch to my Pixel 4 using a 'tandard' USB-C <-> USB-C cable that the touch started charging! Hadn't expected that, and didn't really want to do that because it was already low in battery status.

I suppose the only way to prevent this from happening would be to use a data-only USB-C <-> USB-C cable. Do they even exist??

I use the Serial USB Terminal app, by the way.

Bart.

[Jürgen Müller]

Hi Bart,

 

I noticed that when I connected the Enigma touch to my Pixel 4 using a 'tandard' USB-C <-> USB-C cable that the touch started charging! Hadn't expected that, and didn't really want to do that because it was already low in battery status.

 

I suppose the only way to prevent this from happening would be to use a data-only USB-C <-> USB-C cable. Do they even exist??

 

I think that is driven by the low-level USB implementation on the phone. It detects that the USB port should act as a Host (since a Device was connected) and decides to be a proper host and supply power too. I don’t think I can control that behaviour from the Device (Enigma) side, and even the apps on the phone probably can’t change it.

 

Turns out you can get “power blockers”, but they are a bit exotic. (“Data blockers” for charging without the risk of attacks are more common.) I only found a USB-A version in a quick search: https://www.amazon.de/PortaPow-USB-Power-Blocker-Daten-keine-Stromversorgung/dp/B094FYL9QT?th=1.

 

Best,

Jürgen