lpcware

USB data stream stops

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by mattes on Fri Mar 07 18:08:56 MST 2014
Working on the 11u14 and try to keep the USB communication (CDC) sane.
Start sending out data  to the PC and I use a simple 'cat /dev/TTYACM0' (or terminal program)
to display/receive the data. 

Once the program stops and restarts it will not receive any more data.
The debugger says it is somewhere in the USB stack.

I am currently do not have any event controls built on the 11u14
Looking into that I noticed that:
    Event_USB_Device_Connect and Event_USB_Device_Disconnect are never firing

I see other event coming though, like
   Event_USB_Device_Device_Configuration
   Event_USB_Device_ControlRequest
   Event_CDC_Device_LineEncodingChanged.

Any explanation why _connect and _disconnect are not seen.

What is the recommended way to keep the USB stack healthy and allow the PC software to
close the serial device and reopen it.

How do i know on the 11u14 side when the PC side is opening the device?

Sorry for all the Q, but I am kinda noob with USB stuff.

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