JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

tralamazza — Thu, 01 Nov 2018 15:26:07 GMT

I found that the PlatformIO udev rules were causing this exact problem for me.

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Fri, 16 Feb 2018 17:22:49 GMT

The latest at that link is "J-Link...170724.bin" That looks a lot like at datestamp of Jul 24 2017 (?)

I tried copying it over several times. One time, the device did reset. I am not 100% sure which section of dmesg this was, so can't tell 100% it did a full re-enumeration. The other times (I tried 5 times, power cycling the device each time):

### unplug USB

[1528937.666008] usb 1-5.2: USB disconnect, device number 114

### plug it back in

[1528941.983432] usb 1-5.2: new high-speed USB device number 115 using xhci_hcd
[1528942.084148] usb 1-5.2: config 1 interface 1 altsetting 0 bulk endpoint 0x83 has invalid maxpacket 64
[1528942.084153] usb 1-5.2: config 1 interface 1 altsetting 0 bulk endpoint 0x4 has invalid maxpacket 64
[1528942.084642] usb 1-5.2: New USB device found, idVendor=1366, idProduct=1015
[1528942.084646] usb 1-5.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[1528942.084649] usb 1-5.2: Product: J-Link
[1528942.084651] usb 1-5.2: Manufacturer: SEGGER
[1528942.084654] usb 1-5.2: SerialNumber: 000683350409
[1528942.087099] cdc_acm 1-5.2:1.0: ttyACM0: USB ACM device
[1528942.088279] usb-storage 1-5.2:1.3: USB Mass Storage device detected
[1528942.088501] scsi host6: usb-storage 1-5.2:1.3
[1528943.108201] scsi 6:0:0:0: Direct-Access     SEGGER   MSD Volume       1.00 PQ: 0 ANSI: 4
[1528943.109065] sd 6:0:0:0: Attached scsi generic sg1 type 0
[1528943.109240] sd 6:0:0:0: [sdb] 21829 512-byte logical blocks: (11.2 MB/10.7 MiB)
[1528943.109599] sd 6:0:0:0: [sdb] Write Protect is off
[1528943.109604] sd 6:0:0:0: [sdb] Mode Sense: 0b 00 00 08
[1528943.109898] sd 6:0:0:0: [sdb] No Caching mode page found
[1528943.109906] sd 6:0:0:0: [sdb] Assuming drive cache: write through
[1528943.113960]  sdb:
[1528943.115242] sd 6:0:0:0: [sdb] Attached SCSI removable disk

### enumeration finished, ubuntu auto-mounts sdb
### copy the J-Link OB-SAM3U128-V2-NordicSemi 170724.bin over

[1528962.079410] usb 1-5.2: reset high-speed USB device number 115 using xhci_hcd
[1528962.180672] cdc_acm 1-5.2:1.0: ttyACM0: USB ACM device

### no other activity

The one time the device auto-reset, /dev/sdb was disconnected (as would be expected) and eventually auto-mounted again after it re-enumerated. With this case, the .bin file was no longer present in sdb

The remainder of the times, which all had the exact dmesg above, sdb remained mounted, and the bin file remained until i power cycled via the usb cable.

After this, firing up JLink again, i see the same result:

$JLinkExe -device nrf52840_xxaa -if swd -speed 1000
SEGGER J-Link Commander V6.30c (Compiled Feb  9 2018 17:22:34)
DLL version V6.30c, compiled Feb  9 2018 17:22:28

Connecting to J-Link via USB...Updating firmware:  J-Link OB-SAM3U128-V2-NordicSemi compiled Jan 12 2018 16:05:20
Replacing firmware: J-Link OB-SAM3U128-V2-NordicSemi compiled Jul 24 2017 17:30:12
FAILED: Communication timed out - Can not execute firmware update

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

ivansanchez — Fri, 16 Feb 2018 08:35:21 GMT

No, look at the normal case. There are four interface descriptors: two for USB-CDC-ACM (the serial port) with class/subclass 2/2 and 10/0; one for the mass storage with class/subclass 8/6, and one for the propietary jlink protocol with class/subclass 255/255. It's perfectly legal for a USB device to have many interfaces. It's also legal for a USB device to re-enumerate itself with different interfaces and different descriptors. (And yeah, it's a PITA when those changes are not intended by an user)

Keep in mind that you can enable/disable the mass storage interface and the USB-CDC-ACM interface as described in this bit of documentation for the Zephyr project.

It's weird that the mass storage and USB-CDC-ACM interfaces are disabled in a segger without an explicit request to disable them, though.

I must suggest upgrading the segger firmware manually through the mass storage interface - get segger firmware files from here and copy them to the mass storage volume. The board should reset after that, and hopefully you will **not** see the string "J-Link OB-SAM3U128-V2-NordicSemi compiled Jul 24 2017 17:30:12" when running JLinkExe.

I mean, it's worth a try.

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Thu, 15 Feb 2018 23:20:01 GMT

Yes, the above post is BEFORE trying to touch the part via the nordic tools; Here is the same lsusb AFTER the device spontaneously re-enumerates (sans ttyACM). The Interface descriptor appears to be 0xFF?

Bus 001 Device 104: ID 1366:0101 SEGGER J-Link PLUS
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  idVendor           0x1366 SEGGER
  idProduct          0x0101 J-Link PLUS
  bcdDevice            1.00
  iManufacturer           1 SEGGER
  iProduct                2 J-Link
  iSerial                 3 000683350409
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           32
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          4 Configuration
    bmAttributes         0x80
      (Bus Powered)
    MaxPower              100mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceProtocol    255 Vendor Specific Protocol
      iInterface              5 J-Link
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               1
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               1
Device Qualifier (for other device speed):
  bLength                10
  bDescriptorType         6
  bcdUSB               2.00
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  bNumConfigurations      1
Device Status:     0x0000
  (Bus Powered)

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

ivansanchez — Thu, 15 Feb 2018 08:59:07 GMT

This tiny bit here:

      bFunctionClass          2 Communications
      bFunctionSubClass       2 Abstract (modem)
      bFunctionProtocol       0 None

tells me that, in fact, the USB device has a CDC ACM interface. The cdc_acm kernel driver should pick that up on re-enumeration, and create the /dev/ttyACM* node, and then let udev handle it (to create symlinks under /dev/serial/*).

In those cases when the devkit reenumerates and /dev/ttyACM0 doesn't appear, please run lsusb again, and check for the above lines in the interface descriptors. Also confirm that the cdc_acm kernel module is loaded ("lsmod"), and that it does **not** output "cdc_acm 1-1.4.3:1.0: ttyACM0: USB ACM device" on your syslog and on dmesg.

I just want to be sure there are no inconsistencies in how Linux is handling this.

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Thu, 15 Feb 2018 03:40:16 GMT

Since SES worked on Windows, i tried it on Linux. I installed it in a docker container per usual

PITA as your installer does not support a text mode. Can this please be submitted as a feature request? All installers should support text mode.
Note also, since it's a gui program, X must be mapped in. Obviously this doesn't leverage anything 'sandboxing' as in some container use cases - the reason we attempt to put tools in a container is, as mentioned earlier, repeatability, makes bringing new engineers/computers/test-nodes trivial

Anyway, Both Board-A and Board-B flash and run find under SES Linux, in a container.

What's the difference between these two flows? nrf-commandline-tools using JLink differently than SES? Definitely seems like a problem outside my machine .. although I'm not so sure about how i can make a "bug-jar" for you.

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Thu, 15 Feb 2018 02:36:03 GMT

I tracked down a windows PC, and installed Segger Embedded Studio latest (3,34) along with SDK 14.2.0

Flashing and running the example works on both board-A (I wasn't having issues on linux with this board) AND on board-B.

This made me curious if somehow the windows toolchain had put the board back into a good state ... so I tried both on linux again.

Board B: still fails, usb disconnect occurs, device re-enumerates but ACM doesn't come back without power cycle
Board A: programs/run as normal (no change)

unfortunately i just switch to Win; I'll be using pc-ble-driver with a linux host plus other other Linux-specific work.

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Wed, 14 Feb 2018 15:59:29 GMT

pasting instead of attaching:

Bus 001 Device 085: ID 1366:1015 SEGGER 
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass          239 Miscellaneous Device
  bDeviceSubClass         2 ?
  bDeviceProtocol         1 Interface Association
  bMaxPacketSize0        64
  idVendor           0x1366 SEGGER
  idProduct          0x1015 
  bcdDevice            1.00
  iManufacturer           1 SEGGER
  iProduct                2 J-Link
  iSerial                 3 000683350409
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength          121
    bNumInterfaces          4
    bConfigurationValue     1
    iConfiguration          4 Configuration
    bmAttributes         0x80
      (Bus Powered)
    MaxPower              100mA
    Interface Association:
      bLength                 8
      bDescriptorType        11
      bFirstInterface         0
      bInterfaceCount         2
      bFunctionClass          2 Communications
      bFunctionSubClass       2 Abstract (modem)
      bFunctionProtocol       0 None
      iFunction               5 CDC
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         2 Communications
      bInterfaceSubClass      2 Abstract (modem)
      bInterfaceProtocol      1 AT-commands (v.25ter)
      iInterface              5 CDC
      CDC Header:
        bcdCDC               1.10
      CDC Call Management:
        bmCapabilities       0x03
          call management
          use DataInterface
        bDataInterface          1
      CDC ACM:
        bmCapabilities       0x06
          sends break
          line coding and serial state
      CDC Union:
        bMasterInterface        0
        bSlaveInterface         1 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x87  EP 7 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0008  1x 8 bytes
        bInterval               8
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass        10 CDC Data
      bInterfaceSubClass      0 Unused
      bInterfaceProtocol      0 
      iInterface              6 CDC DATA interface
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x83  EP 3 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               1
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x04  EP 4 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               1
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceProtocol    255 Vendor Specific Protocol
      iInterface              7 BULK interface
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               1
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               1
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        3
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass         8 Mass Storage
      bInterfaceSubClass      6 SCSI
      bInterfaceProtocol     80 Bulk-Only
      iInterface              8 MSD interface
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x85  EP 5 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               1
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x06  EP 6 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               1
Device Qualifier (for other device speed):
  bLength                10
  bDescriptorType         6
  bcdUSB               2.00
  bDeviceClass          239 Miscellaneous Device
  bDeviceSubClass         2 ?
  bDeviceProtocol         1 Interface Association
  bMaxPacketSize0        64
  bNumConfigurations      1
Device Status:     0x0000
  (Bus Powered)

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Wed, 14 Feb 2018 15:57:25 GMT

huh ... i posted a txt file of this dump here yesterday ... I don't see it now?

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Wed, 14 Feb 2018 15:55:41 GMT

I've tried native-linux, and in a docker container with the necessary devices and permissions mapped.

FWIW, my normal workflow is from a docker container, as it makes tasks such as rolling new versions, sharing a consistent dev env amoung the team, and standing up automated test boxes trivial compared to local install. From within a container, i've had no problem with other boards.

I'll look around for a box i can install windows on. Is there a preferred version?

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

Håkon Alseth — Wed, 14 Feb 2018 10:19:04 GMT

Are you running linux in a VM or native?

Have you tried running JLinkExe as root, or updating the firmware on a windows PC?

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Tue, 13 Feb 2018 23:12:16 GMT

Hi Hakon - Re-running with the profile you suggest has slightly different output, but the same end-result of the device dropping off / re-enumerating on USB. nrf52840_xxaa is recognized; connecting to it looks like it's trying to flash segger bits automatically (presumably this is fw on the seggar part; i'm not familiar with any of that)

$ JLinkExe -device nrf52840_xxaa -if swd -speed 1000

SEGGER J-Link Commander V6.30c (Compiled Feb  9 2018 17:22:34)
DLL version V6.30c, compiled Feb  9 2018 17:22:28

Connecting to J-Link via USB...Updating firmware:  J-Link OB-SAM3U128-V2-NordicSemi compiled Jan 12 2018 16:05:20
Replacing firmware: J-Link OB-SAM3U128-V2-NordicSemi compiled Jul 24 2017 17:30:12
FAILED: Communication timed out - Can not execute firmware update
J-Link>

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Tue, 13 Feb 2018 22:40:58 GMT

typo, thanks.

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

ivansanchez — Tue, 13 Feb 2018 09:54:39 GMT

Could you please post the result of running "lsusb -v -d 1366:"? That will display the USB descriptors for any Segger IMCUs connected through USB.

Please note that a Segger IMCU can enable/disable mass storage and USB-CDC-ACM, as noted in http://docs.zephyrproject.org/tools/nordic_segger.html#nordic-segger-msd . Also be aware that the USB Product ID (0x0101 in your case) changes as the IMCU is configured (as you can see from having a look at /etc/udev/rules.d/99-jlink.rules )

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

ivansanchez — Tue, 13 Feb 2018 09:48:05 GMT

A quick note to the side: ACM doesn't stand for "Abstract compute module", it stands for "Abstract control model", as per the USB specifications. See https://rfc1149.net/blog/2013/03/05/what-is-the-difference-between-devttyusbx-and-devttyacmx/ for more info.

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

Håkon Alseth — Tue, 13 Feb 2018 07:08:09 GMT

Hi,

Try connecting with device profile "nrf52840_xxaa".

It looks like your firmware has already been updated successfully:

Firmware: J-Link OB-SAM3U128-V2-NordicSemi compiled Jan 12 2018 16:05:20

You can now write "?" for help, and use commands like "loadfile /path/to/hex.hex" to program the device and "erase" to erase the flash.

I suspect that nrfjprog will also work now that the fw has been updated.

Cheers,

Håkon

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Mon, 12 Feb 2018 22:31:28 GMT

I had adapted the above JLinkExe command line from the script (I believe @Hakon) linked folks to in a different question, https://github.com/ssfrr/nrfjprog.sh/blob/master/nrfjprog.sh

If i change the --device param from nrf52840 to just nrf52, the connect does work. It appears that simple commands like reset do as well.

What is the JLinkExe command to erase / re-flash the 52840?

Thank you for your help.

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Mon, 12 Feb 2018 22:25:09 GMT

Also, I just noticed a new Segger version has been released; v6.30c (above is v6.30b).

The error is identical with the new revC

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

sdpan — Mon, 12 Feb 2018 22:20:14 GMT

It doesn't look like JLink knows about nrf52840 yet ??

Side note - I have googled around several times for this, but cannot find any good/current docs/tutorials for the native Segger utilities. I understand Nordic uses these under the hood .. but please if you need me to run them, pass me an appropriate command line. Thank you!

$ JLinkExe -device nrf52840 -if swd -speed 1000 
> connect

SEGGER J-Link Commander V6.30b (Compiled Feb  2 2018 18:38:58)
DLL version V6.30b, compiled Feb  2 2018 18:38:53

J-Link connection not established yet but required for command.
Connecting to J-Link via USB...O.K.
Firmware: J-Link OB-SAM3U128-V2-NordicSemi compiled Jan 12 2018 16:05:20
Hardware version: V1.00
S/N: 683889153
VTref = 3.300V
The selected device "NRF52840" is unknown to this version of the J-Link software.

Please make sure that at least the core J-Link shall connect to, is selected.
Proper device selection is required to use the J-Link internal flash loaders
for flash download or unlimited flash breakpoints.

For some devices which require a special handling, selection of the correct device is important.
No valid device has been selected.

RE: JLink serial (ttyACM0 over usb) drops out, usb device re-enumerates but ttyACM isn't found

Håkon Alseth — Mon, 12 Feb 2018 07:20:13 GMT

Hi,

I suspect this might be the reason for the stability issues you're seeing:

[quote user=""]Updating firmware: J-Link OB-SAM3U128-V2-NordicSemi compiled Jan 12 2018 16:05:20
Replacing firmware: J-Link OB-SAM3U128-V2-NordicSemi compiled Jul 24 2017 17:30:12
JLinkARM.dll OpenEx returned error 'Communication timed out - Can not execute firmware update'.[/quote]

Have you tried upgrading the fw using segger's "JLinkExe" program? If you installed their .deb package, it should be in your $PATH.

Best regards,

Håkon