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USB raw access


#1

Hello, just wondering whether it would be a problem for GHI to provide lower access to both the USB host & client ports, like raw reading and writing from/to the serial bus, perhaps with a Stream or just Read/Write methods?

I am talking about the ability to read and write packets including the setup ones, including CRC etc.
I guess the code must be already there…

Jan


#2

Possible but I am not sure what exactly you needs done and raw USB can’t do. Maybe explain more if possible please.


#3

Sure, that would be helpful for testing and monitoring devices/hosts.

The application I was trying to do recently was just an USB proxy, that would be logging the communication between arbitrary client and host.

Even assuming both device and hosts are already certified and working devices, I was unable to finish it. If you believe this can be done with the current GHI’s model I would be more than happy to discuss the code. :slight_smile:


#4

I thought about this personally, a (somewhat) USB analyzer. The problem is that most chips’s USB client peripheral will not offer control-EP on every single socket.

If all you need is very low access then it maybe better to go direct to the chip through RLP or even not use NETMF altogether.

Another good option is to add MAX3421 over SPI and then you can control it anyway you like over SPI.


#5

Yes, kind of. That’s a very interesting point I was unaware of (that the reason why MF does not allow me to access the control endpoint might be because most hardware does not allow it).

Thanks for the MAX3421 tip, seems like a nice workaround for the lowest stuff if you do not need the stack!