Arduino Micro: /dev/ttyACM0 disappear after few second

Development Tools IDE 1.x
1

Hi all,

i have a proble with my arduino micro board on linux. When i plug it into my laptop, the device /dev/ttyACM0 is registered correctly, and this is what i get from dmesg:

[ 720.653221] cdc_acm 2-1.2:1.0: usb_probe_interface
[ 720.653225] cdc_acm 2-1.2:1.0: usb_probe_interface - got id
[ 720.653237] cdc_acm 2-1.2:1.0: ttyACM0: USB ACM device
[ 720.654151] usb 2-1.2: adding 2-1.2:1.1 (config #1, interface 1)

But after few seconds the /dev/ttyACM0 device disappear, and what i got on dmesg is:

[ 728.316212] usb 2-1.2: USB disconnect, device number 11
[ 728.316217] usb 2-1.2: unregistering device
[ 728.316223] usb 2-1.2: unregistering interface 2-1.2:1.0
[ 728.316382] usb 2-1.2: unregistering interface 2-1.2:1.1
[ 728.316423] usb 2-1.2: usb_disable_device nuking all URBs
[ 728.420514] hub 2-1:1.0: debounce: port 2: total 100ms stable 100ms status 0x10

Any Idea?
The other board Arduino UNO is working well i have this problem only with my micro board.

2

It seems that i have the same problem even on windows (a least when i plug the micro board i heard the ta-da sound of a plugged device, and few seconds later, i heard the te-de sound of an unplugged device :slight_smile: )

and the serial monitor works only for few seconds... (so i suppose the same happens on linux)

3

Hi finarfin,

I'm experiencing the exact same problem with an Arduino Micro on linux. Did you finally fix this issue?

This is my dmesg output for reference:

[21468.142733] usb 4-3: new full-speed USB device number 25 using ohci-pci
[21468.317840] usb 4-3: New USB device found, idVendor=2341, idProduct=0037
[21468.317844] usb 4-3: New USB device strings: Mfr=2, Product=1, SerialNumber=0
[21468.317846] usb 4-3: Product: Arduino Micro   
[21468.317847] usb 4-3: Manufacturer: Arduino LLC
[21475.522837] usb 4-3: USB disconnect, device number 25
[21476.313435] usb 4-3: new full-speed USB device number 26 using ohci-pci
[21476.490541] usb 4-3: New USB device found, idVendor=2341, idProduct=8037
[21476.490543] usb 4-3: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[21476.490545] usb 4-3: Product: Arduino Micro   
[21476.490547] usb 4-3: Manufacturer: Arduino LLC
[21476.503585] input: Arduino LLC Arduino Micro    as /devices/pci0000:00/0000:00:12.0/usb4/4-3/4-3:1.2/input/input38
[21476.503709] hid-generic 0003:2341:8037.000D: input,hidraw0: USB HID v1.01 Mouse [Arduino LLC Arduino Micro   ] on usb-0000:00:12.0-3/input2
[21477.150891] usb 4-3: USB disconnect, device number 26
4

To anyone still stumbling upon this issue, one thing that worked for me was to upload a very short program (blink in my case) very quickly during the 8 seconds the board stays connected. It looks like some boards can stay stucked in bad states but if you manage to overwrite the program before it starts, you can be saved.

Praises be to the bootloader.

5

@YvesQuemener

I'm always surprised how people manage to find 6 year old threads :wink: