USB OTG

Hi all,

I have an application that I have been testing with the standard Raspberry Pi 4 and Zero W models on the bench in which they emulate a HID keyboard device via USB OTG. Are any of the Revolution Pi variants capable of acting as a USB OTG device by presenting the Compute Module 3’s USB port as a HID device?

Hello packinpennies, to sum up - could work.

The USB OTG functionality might work with the Micro USB on the front.
Please analyze the circuitry which you can find here in the downloads section.
It is also important that no voltage is applied here during the boot process, because
otherwise the device will not boot.

Ok, let's assume the circuit works, then USB on the front panel plus Ethernet would not work anymore!
Then you don't have a connection to the RevPi Core anymore.
But with the Connect there is a 2nd eth interface, which is not connected via USB but via SPI,
there might be a connection.
If your program is started that simulates the HID device before the Micro USB connects
and if Ethernet and the two USB ports are not needed afterwards, it might work.

Hi dirk,

Thanks for letting me know.

We will also require the USB host ports and Ethernet, and it is my understanding that the Compute Module only has a single USB port that can either act as a host or device, so it looks like this may not work as intended.

Hi packinpennies,
so this is the problem you require USB host and Ethernet.
But this in this will also not work with a RaspberryPi either.

As far as I know Raspberry Zero and Rasperry 4 are capable of working as USB device.
In contrary to Raspberry 3 they are using a USB Type-C connector which is using
a different signaling approach.

Will Revolution Pi support these signals when switching over to Compute Module 4?