How use usb data line without usb core

[Vlad Mokhnachov]

Hi, Nordic! We have connected gpio pins to usb data line pins for using usb or i2c in different times. But even if USB core disconnected, usb lines hinder for i2c lines. Is it possible connect usb d+ and d- to GPIO?

[Jørn]

Hello Vlad

As RK has stated none of the GPIO of the nRF52840 supports USB, and the USB pins are exclusively used for USB. So if you want to use the GPIO for USB do that you would have to bitbang it somehow, though I'm not sure if that would be possible.

Unfortunately we do not have any examples or reference code for something like this. I have seen people claim to have bitbanged USB on ARM M0 processors, however for our products you would have to worry about the SoftDevice using part of the processor time as well.

To my knowledge USB has never been bitbanged on any of our products, so I'm afraid I don't have any further advice on how to achieve something like that.

Best regards

Jørn Frøysa

[Jørn]

Ah yes of course, I believe you're right. I will look further into this.