Hologram Nova (SARA-R410-02B) problems on Ubuntu


There appears to be an interaction between ubuntu Linux modem manager and the SDK;

Ubuntu 18.04 (in VM under MacOS) with results:

dhoward@ubuntu:~$ sudo mmcli -L
Found 1 modems:
/org/freedesktop/ModemManager1/Modem/0 [u-blox] SARA-R410M-02B

dhoward@ubuntu:~$ nmcli d
ens33 ethernet connected Wired connection 1
ens38 ethernet connected Wired connection 2
cdc-wdm0 modem disconnected –
lo loopback unmanaged –

dhoward@ubuntu:~$ sudo hologram modem signal
ERROR: Unable to detect a usable serial port

dhoward@ubuntu:~$ lsusb
Bus 001 Device 003: ID 05c6:90b2 Qualcomm, Inc.
Bus 001 Device 002: ID 0e0f:000b VMware, Inc.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 004: ID 0e0f:0008 VMware, Inc.
Bus 002 Device 003: ID 0e0f:0002 VMware, Inc. Virtual USB Hub
Bus 002 Device 002: ID 0e0f:0003 VMware, Inc. Virtual Mouse
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

dhoward@ubuntu:~$ dmesg | tail
[ 109.274882] usbserial: USB Serial support registered for GSM modem (1-port)
[ 109.274961] option 1-2:1.0: GSM modem (1-port) converter detected
[ 109.275022] usb 1-2: GSM modem (1-port) converter now attached to ttyUSB0
[ 109.275065] option 1-2:1.2: GSM modem (1-port) converter detected
[ 109.275101] usb 1-2: GSM modem (1-port) converter now attached to ttyUSB1
[ 109.275740] usbcore: registered new interface driver cdc_wdm
[ 109.287898] qmi_wwan 1-2:1.3: cdc-wdm0: USB WDM device
[ 109.288049] qmi_wwan 1-2:1.3 wwan0: register ‘qmi_wwan’ at usb-0000:02:03.0-2, WWAN/QMI device, ee:70:2b:9d:ac:e1
[ 109.288073] usbcore: registered new interface driver qmi_wwan
[ 109.297247] qmi_wwan 1-2:1.3 wws35u2i3: renamed from wwan0

dhoward@ubuntu:~$ ls /dev/ttyUSB*
/dev/ttyUSB0 /dev/ttyUSB1

dhoward@ubuntu:~$ sudo mmcli -v -m 0 -d
[29 Oct 2018, 12:28:55] [Debug] ModemManager process found at ‘:1.5’
[29 Oct 2018, 12:28:55] [Debug] Assuming ‘0’ is the modem index
[29 Oct 2018, 12:28:55] [Debug] Modem found at ‘/org/freedesktop/ModemManager1/Modem/0’

[29 Oct 2018, 12:28:55] [Debug] Synchronously disabling modem…
successfully disabled the modem

after which the hologram CLI works reliably

dhoward@ubuntu:~$ sudo hologram modem signal
Signal strength: 31,99


Hey @davidhoward,

Looks like you need to disable ModemManager, or just wait for ModemManager to finish its scan before running our SDK. Our SDK is a modem manager and you can’t run more than one at a time.



Yes that is the case. I have removed it for now. sudo apt autoremove modemmanager