STM32F4 Resetting itself (Nucleo 64)

[Andres Cao]

Posted on April 14, 2017 at 00:58

Hi!

I have a Nucleo64-446RE and every 5/10 minutes the board resets itself.

I'm using the Virtual COM to send data to my PC and plot it (among many other things), and when the board resets I lose the Serial connection. I need to re-open it in order to plot again. If after this reset I want to program the microcontroller I get the ''Unable to reset target'' message for which I need to unplug and replug the USB(which is also powering the board). I'm using the System Workbench for STM32.

Here's an oscilloscope picture of the NRST pin (blue), which confirms the reset. The red trace is a 3.3V pin, which shows there are no power issues. 

Can you please help me debug this reset?

As I understand, it can't be a Hard Fault because (I think) in that case the system wouldn't reset but end up in an infinite loop. I haven't implemented any of the error handlers, but I think they're implemented by default with weak attributes.

Watching the following image:

From external sources:

• Definitely I'm not pressing the reset button
• The ST-LINK could be resetting. How likely is this, why would it? Given that Virtual Com connection is lost it could be the case, since if I press the reset button the Virtual Com connection is not lost.

From internal sources:

• WWDG is not activated
• IWDG is not activated
• Red trace would prove it's not a power reset
• There's no lower-power mode being used.
• Software reset, this would be the only option. What causes a software reset?

Thank you very much in advance for all your input!

Cheers,

Andrés

[Tesla DeLorean]

Posted on April 22, 2017 at 16:54

I don't think any of those devices attempts to spoof a mass-storage controller.

Definitely some interaction. If it still fails on the Dell's when booted from a Linux Live CD I'd suspect the hardware, but most probably a software interaction from something installed on the Dell. Toshiba, Compaq and Dell systems were always tech support nightmares.

[Gregory Hancock]

Posted on April 22, 2017 at 19:21

It has something to do with the USB Mass Storage system. I disconnected the mbed drive using 'Safely Remove Hardware and Eject Media' taskbar icon menu item 'Eject NODE_L432KC (E:)'. The drive unmounted. A few minutes later, Windows 10 autonomously remounted the drive. The Nucleo board reset at exactly the same moment.

Next step: figure out why Windows is remounting the drive.

By the way, real-time antivirus is off. The machine is active the entire time -- no screensaver or power-down.

[Gregory Hancock]

Posted on April 22, 2017 at 19:58

Disabling the 'MBED Microcontroller USB Device' under 'Disk drives' in Windows Device Manager seems to have solved the problem. That's not an ideal solution, but it's an acceptable temporary workaround.

[Tesla DeLorean]

Posted on April 23, 2017 at 18:52

If it is truely Dell unique, review what filter drivers are installed and attaching themselves to the USB Storage nodes.

[Brian Tetzlaff]

Posted on April 24, 2017 at 17:43

I am running Windows 7 on both of the Dell laptops that have this problem.

One is a Dell Precision 3510 and the other is a Dell Precision 7710.

[Tesla DeLorean]

Posted on April 24, 2017 at 18:20

May be you can identify what Upper/Lower Filters you have attached to the USB Storage class devices.

[Brian Tetzlaff]

Posted on April 24, 2017 at 19:16

MBED microcontroller USB Device Properties 'Details' Tab

Property: Class upper filters

Value: PartMgr

Property: Class lower filters

Value: iaStorF, stdcfltn

[Brian Tetzlaff]

Posted on April 24, 2017 at 19:21

If it helps, on one of the Dell laptops that does not have this problem, under Class lower filters, it only has the stdcfltn filter listed.

[S.Ma]

Posted on April 24, 2017 at 19:25

In the debugger st link settings, tgere should be some options on how it interacts by swd and how the rst pin behaves. Try the options to find out if one configuration is closer to your needs.

[Gregory Hancock]

Posted on April 24, 2017 at 19:51

I uninstalled the Dell support/diagnostic tools (OEMed from PCDoctor) before I read these latest comments, and now the problem seems to be gone. For what it's worth, here is my (working) USB device configuration now:

Class lower filters: EhStorClass, stdcfltn

Class upper filter: partmgr

Driver files:

c:\windows\system32\DRIVERS\disk.sys - Microsoft Corporation, 10.0.14393.0 (rs1_release.160715-1616)

c:\windows\system32\drivers\EhStorClass.sys - Microsoft Corporation, 10.0.14393.0 (rs1_release.160715-1616)

c:\windows\system32\drivers\partmgr.sys - Microsoft Corporation, 10.0.14393.0 (rs1_release.160715-1616)

c:\windows\system32\DRIVERS\stdcfltn.sys - ST Microelectronics, 1.00.00.12

I could reinstall the Dell support tools to further test this, but that seems counterproductive at this point.