EM7455 Wake on WAN via USB?


I have a question for which I can’t find the answer in the available documents. For the sake of this post, let’s consider an externally-powered, fully USB3.0-based implementation of the module.

If the WAKE_ON_WAN# signal is not used, can a wake request be sent over USB to the host by the EM7455 module? (Also known as a “Remote Wake-up” or “Upstream Resume”)


AirPrime_MC73xx_USB_Driver_Developers_Guide_Rev1_1.pdf ( assuming similarities), lists the DIAG interface as having bmAttributes: 0xE0. This link (otherwise unrelated) breaks down bmAttributes as follows:

  • Bit 7 is always 1
  • Bit 6 is self-powered,
  • Bit 5 is remote wake capable
  • Bit 4:0 are always 0

Therefore the DIAG interface, if nothing else, offers remote wake capability.

Upon looking again, I noticed in Section C of the Technical Specification of EM7455 to “Make sure the host USB driver supports remote wakeup, resume, and suspend operations, and serial port emulation.”

Presumably this means that WAKE_ON_WAN# is not necessary.