USB OTG in CM3

[WisePi]

Hi,

Has anyone been able to use the USB OTG on the RPi CM3? I'm following https://gist.github.com/gbaman/50b6cca61dd1c3f88f41 without success. Also, I noticed that when I connect a host computer via USB OTG to the RPi port USB Slave, the Linux terminal becomes unresponsive. This happens with the jumper in both EN and Disable positions.

Any help would be greatly appreciated.

Thanks

[christian.bao]

I was able to get the USB OTG in the RPI CM3+ by following the instructions by Adafriut: https://learn.adafruit.com/turning-your ... usb-gadget.

Make sure to understand the breakout board that you are using. For example, the IO board I am using has a resistor connected to the OTG_ID pin to ground, putting the RPI CM3+ in host mode all the time. I had to remove that resistor to be able to enable gadget mode. The RPI CM3+ has an internal pull-up resistor for the OTG_ID pin. They don't specify that in the datasheet, but an engineer from the org confirmed this in another thread I read. Now, when I need to put the CM3+ in device mode I simply ground the OTG_ID pin.

I used the latest image from the RPI website, not Jessie or Jessie Lite as listed in the Adafruit website. It is understood that those changes have been propagated to the latest release. And although I have been able to enumerate as a COM port, the actual communications are not working. I even tested on a RPI Zero and it was doing the same. Not sure if this is a mistake on my setup or a change in the software, I need to investigate further.

Anyway, it works, just how well is another question. I will investigate the g_ether module next and see if that works better.

Good luck!