Andreas Benamou

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11 years, 8 months ago.

KL-25Z Reports 0ma in firmware in XP

I'm seeing that in XP my KL-25Z with mbed firmware is not recognized on cold boot in Windows XP when running my software to make it a USBHID device.

In the device manager in XP it reports the power requirements as 0ma, which seems like that might be the issue. Can someone who works at mbed comment? I see a new USB firmware was posted a week or so ago, so I presume there is work being done on the firmware.

Bump just in case my question to the answer didn't get noticed - would be great to figure out the USB issues with detection soon.

posted by Andreas Benamou 23 Jan 2014

2 Answers

Neil Thiessen
11 years, 8 months ago.

The reported power requirements should not be an issue, I've seen a lot of USB hard drives that report 0mA as well.

Accepted Answer

For anyone reading, the issue turned out to be rather obscure. I was using PTA4, and it was randomly detecting resistance on the pin causing the CPU to reset.

The fix is documented in this thread:

http://mbed.org/questions/1387/How-can-I-access-the-FTFA_FOPT-register-/

posted by Andreas Benamou 30 Jan 2014
Andreas Benamou
poster
11 years, 8 months ago.

Thanks for the quick response! Any idea why the board wouldn't be recognized in XP on cold-boot? And a USB3 port doesn't seem to recognize it at all.

Sorry, I meant to post that as a comment, not an answer. Have you tried plugging it in on another version of Windows? The library was just updated a few minutes ago to solve some string issues I was experiencing, but I doubt this would keep it from enumerating.

posted by Neil Thiessen 23 Jan 2014

Thanks, yes I have also seen this issue on Win 7 but doesn't happen all the time. I also can reproduce the issue using sleep. My steps were:

1. Plug in 25Z, let Windows detect - confirm it's working as USB HID 2. Put computer to sleep (Windows 7) 3. Resume from sleep 4. After resume board is no longer recognized

Might be a related issue, or an easy way to reproduce the cold-start issue. Can you try this and let me know if you can reproduce the problem?

posted by Andreas Benamou 23 Jan 2014

USB3 ports are indeed a problem. You apparantly have USB2 ports also, if someone ends up here who only has USB3 ports: a USB2 hub between your PC and the KL25 will solve it most likely.

That said I checked that the K20, which is the interface IC, seems to have a pretty much identical USB peripheral. It might be a newer revision, or it might be because it uses slightly different code, but that does work with USB3. Has anyone tried it with a different USB stack on the KL25Z if it worked with USB3.0?

posted by Erik - 23 Jan 2014

Just did an experiment with my EA LPC11U35 QuickStart Board, and it worked just fine on a USB3.0 port running the USBHID Hello World app. This must be specific to the KL25Z.

posted by Neil Thiessen 23 Jan 2014

Who is responsible for investigating and fixing these issues with mbed and this board? Is the firmware source somewhere to debug or will mbed need to fix? Thanks.

posted by Andreas Benamou 23 Jan 2014