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1
USB / Re: MAUSB Compliance Testing
« Last post by Jan Axelson on January 18, 2017, 10:17:28 am »
The USB-IF has released compliance tests for other major device classes, so media agnostic USB will likely have something eventually. I have no specific knowledge of if or when however.
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USB / MAUSB Compliance Testing
« Last post by DD on January 18, 2017, 12:49:26 am »
Will there be any tool like USB3CV Tool for MAUSB Testing?
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USB / Re: Linux xhci "WARN Event TRB for slot x ep y with no TDs queued?"
« Last post by Jan Axelson on January 14, 2017, 11:45:30 am »
If the host is resetting all of the USB ports, something has gone very wrong with communications.

What is the host platform and what part of it are you developing?
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USB / Linux xhci "WARN Event TRB for slot x ep y with no TDs queued?"
« Last post by rick7712 on January 14, 2017, 11:10:56 am »
Hi,

I'm debugging usb issues on my platform which is running Linux, and I quite often encounter messages like this during file copying on usb drives:

[79078.920948] xhci_hcd 0000:04:00.0: HC gave bad length of 4083 bytes left
[79139.522693] xhci_hcd 0000:04:00.0: WARN Event TRB for slot 3 ep 3 with no TDs queued?
[79139.532536] xhci_hcd 0000:04:00.0: WARN Event TRB for slot 1 ep 2 with no TDs queued?
[79139.542407] xhci_hcd 0000:04:00.0: WARN Event TRB for slot 1 ep 3 with no TDs queued?
[79139.552251] xhci_hcd 0000:04:00.0: WARN Event TRB for slot 4 ep 2 with no TDs queued?
[79139.562110] xhci_hcd 0000:04:00.0: WARN Event TRB for slot 4 ep 3 with no TDs queued?
[79139.571948] xhci_hcd 0000:04:00.0: WARN Event TRB for slot 2 ep 2 with no TDs queued?
[79139.581847] xhci_hcd 0000:04:00.0: WARN Event TRB for slot 2 ep 3 with no TDs queued?
[79140.665814] usb 3-1: reset SuperSpeed USB device number 4 using xhci_hcd
[79141.791780] usb 3-4: reset SuperSpeed USB device number 2 using xhci_hcd
[79142.916747] usb 3-3: reset SuperSpeed USB device number 5 using xhci_hcd
[79144.042481] usb 3-2: reset SuperSpeed USB device number 3 using xhci_hcd


I'm thinking that does the "WARN Event" messages mean the xHC found the Transfer ring is empty? And xHC think it's weird?
And for the reset messages, should I take it as a warning that there's sth bad happened on my USB3.0 link? So the driver try to recover?
Here is the xhci-ring.c: http://ppt.cc/SfNK2

I will also keep reading the xHCI spec to find out the answer of my problem...
Thanks..
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USB / Re: WinUSB Read Pipe
« Last post by Jan Axelson on January 13, 2017, 01:28:03 pm »
Not a pretty technique, but depending on how much time elapses before the fail and how much data you can store, you could stop and restart the analyzer periodically in hopes of catching the error.

Also probably not that useful, but you could try waiting until it fails, then start the analyzer and do another read. It's likely that the driver won't attempt anything on the bus, however.

Make sure your firmware is robust enough that the endpoint is always ready to either NAK or accept data.

If you can slow the transfers by adding delays and the problem goes away, that will tell you something.
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USB / Re: enumeration issues if device is already powered by batteries
« Last post by Bret on January 13, 2017, 11:44:40 am »
This definitely seems like an issue related to power, though not necessarily voltage.  If it's feasible, you should try to measure both current and voltage, and do it at the input to the micro (after all of the switching transistors and regulators and filters and whatever have done their job).  It's even possible you're losing voltage or limiting current through the switching transistor when the batteries are there but not when USB power is there (depending on how the circuitry is designed).
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USB / Re: WinUSB Read Pipe
« Last post by sudheerg_ on January 12, 2017, 11:13:27 pm »
Hi Jan,

Thank You for your reply and time.

I have Advisor T3, my understanding is it has a limitation of how much it can capture. I was not able to configure it to capture for infinite time.

Let me know if any one in this forum know how to configure it to capture for infinite duration. I have used spooled mode available in advisor T3, and I have sufficient hard disk space 700 GB, but the analyzer stops after capturing for some time.

Regards,
GSR
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USB / Re: WinUSB Read Pipe
« Last post by Jan Axelson on January 12, 2017, 09:37:16 pm »
Best is if you can connect a hardware-based protocol analyzer and watch what happens when you try to read data.

It's likely that the device is failing to respond to IN token packets with data or NAK.
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USB / Re: enumeration issues if device is already powered by batteries
« Last post by doctormano on January 12, 2017, 02:16:08 pm »
Thanks for all inputs. Will look into the USB reset to see if there is anything that might explain this issue.
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USB / Re: enumeration issues if device is already powered by batteries
« Last post by doctormano on January 12, 2017, 02:12:41 pm »
Thanks for the response. There is only one regulator providing power to the micro. When USB is connected, it goes through a switching transistor to switch power from batteries to USB. Bypassing this and keeping the micro's input voltage at 3.3 volts doesn't make any difference in the enumeration frequency. Still fails when batteries are present. Monitored the voltage via scope and there is no dip in the voltage when USB cable is connected.
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