USB on Verdin iMX8M Plus

For a new development, we have chosen the Verdin iMX8M Plus module. The module and dev board have already been ordered but have not yet arrived, so everything is “theoretical” at the moment.
However, there have already been a few questions regarding USB, which is why I hope to find an answer here.

  1. The Verdin module should act as a device (USB connection to a tablet). As far as I’ve read, that’s only possible with port 1? Port 2 can only be used as host?
  2. I would then like to operate the port as a DRD. An example is shown in Mr. Lischer’s seminar at 40:55 (Add USB-C to your next carrier board design! - YouTube). Unfortunately, I could not find this example in the specified source. I’m also having a hard time finding example circuits for this application in general. Do you have any recommendations for this or the place where I can find the circuit?
  3. The Verdin Carrier Board Design Guide ( page 25 describes port 1: “This port is usually used in the recovery mode for loading new software onto the module”. Would it be possible in principle to use port 2 for this?
  4. The table also shows that port 1 is only possible up to a maximum of USB 2.0. In the pinout designer, however, I can also select the extra data lanes for port 1. Does the Plus version also support USB 3.x on port 1?

Thank you :slight_smile:

  1. Yes
  2. We can provide a preliminary schematic for this. This will be the design on the new Apalis Eval board as well.
  3. No the recovery USB port is fixed.

The i.MX 8M Plus SoC features two identical USB 2.0 ports which are both OTG capable. However,
in the Verdin standard, only the USB_1 port is an OTG port, while USB_2 is only a host port.
Therefore, it is recommended to use only the USB_1 as an OTG port. The USB_1 port is also used
for the serial mode (recovery mode). Both USB ports of the i.MX 8M Plus SoC feature USB 3.1 Gen
1 SuperSpeed (previously called USB 3.0, backward compatible with USB 2.0). Only USB_2
supports the SuperSpeed signals required for a USB 3.1 Gen 1 capable interface in the Verdin
standard. However, the SuperSpeed signals of the USB_1 interface are available on module-
specific pins. The location of these SuperSpeed signals is not guaranteed to be compatible with
other Verdin modules. Therefore, it is recommended for compatibility purposes to use the USB_1
only with the USB 2.0 signals.

Best Regards,
Matthias Gohlke

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