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9 votes

Difference between PPP, QMI and AT commands

A LTE modem can be presented to the operating system in several ways. The legacy way is to emulate a legacy analog modem: in that case, the modem will present one serial (TTY) interface (/dev/ttyUSB0),...
telcoM's user avatar
  • 98.2k
8 votes
Accepted

How do I spoof different device ID for the purposes of Linux device management?

You can see the module(s) that would be loaded for USB device with vendor:product IDs 1199:9079 with: sudo modprobe -c | grep usb:v1199p9079 The results will be similar to: alias usb:v1199p9079d*dc*...
telcoM's user avatar
  • 98.2k
6 votes

How to disable PIN on a SIM card?

The following commands will allow you to remove SIM CODE from SIM card screen /dev/USB0 Let's assume you have a modem on /dev/ttyUSB0 (check dmesg when you plug your usb to ensure that) The ...
user1707414's user avatar
6 votes

How to get address of connected USB modem?

Probably too late, but it might help others. Wouldn't help you to use mmcli from ModemManager? $ mmcli -L Found 1 modems: /org/freedesktop/ModemManager1/Modem/4 [Lenovo] H5321 gw $ mmcli -m 4 ...
pevik's user avatar
  • 1,483
5 votes
Accepted

USB LTE modem without MAC address?

If I'm not mistake, I don't use RNDIS right now. RNDIS is a Windows-specific network interface driver API. Um, that as nothing to do with what you're doing, right? What might be the reason, that ...
Marcus Müller's user avatar
4 votes
Accepted

Mobile broadband repeatedly connects/disconnects

Okay, I've finally after years of immense frustration managed to solve the problem, which is that NetworkManager is just really buggy about modems. In fact, recently it has gotten worse and even ...
user3188445's user avatar
  • 5,307
4 votes

configure gsm connection using nmcli

It's a year later now and a lot of packages are updated. Using the ModemManager service and mmcli I was able to initialise my ublox SARA-U201. ModemManager already made the connection called "mymodem"....
Pete's user avatar
  • 141
4 votes
Accepted

?z waiting to receive.**B0100000023be50 when I use rz to upload file

What you are seeing is the request (from rz) to its remote side (yours) to initiate a ZMODEM upload. The obvious questions here would be: Are you using a ZMODEM-capable terminal? Are you starting a ...
user's user avatar
  • 29.1k
4 votes

qmicli Cannot set expected data format

Just a silly mistake, I forgot to take the interface down before I execute the command to set the expected format to raw-ip.
aobs's user avatar
  • 191
4 votes

How to get audio in and out of Huawei GSM modems when doing a voice call?

After placing or receiving a call, audio output on the serial device needs to be enabled (each time for each call) by issuing AT^DDSETEX=<number> (for my devices, only AT^DDSETEX=2 is ...
Golar Ramblar's user avatar
4 votes
Accepted

GSM modem - get signal strength

GSM modems can be controlled by a number of different protocols. Because of this, NetworkManager uses a second component called ModemManager to interface with them. On my system, I can do this: $ ...
telcoM's user avatar
  • 98.2k
4 votes

How to verify modem is a fax modem?

Partial answer: Googling for modem drivers for this laptop finds this, which offers an "LSI HDA" driver. Googling for "LSI HDA" indicates that it really seems to be a "High-...
dirkt's user avatar
  • 32.5k
3 votes
Accepted

How do you remove Mobile Broadband Networks from the Gnome menu bar?

After some digging around and some questions in IRC someone pointed out that these connections come from paired bluetooth devices. Simply running: bluetoothctl Brings up a list of all paired ...
Rumbles's user avatar
  • 230
3 votes
Accepted

getting "bad init string" when dialing with wvdial

This wvdial.conf worked on ZTE 3G Modem below: [Dialer Defaults] Modem = /dev/ttyUSB0 Init1 = ATZ Init3 = AT+CGDCONT=1,"IP","apnname" Phone = *99***1# Username = user Password = user New PPPD = ...
supriady's user avatar
  • 167
3 votes
Accepted

Convert sound encoded in RTTY 45.45 baud using minimodem

I'm not familiar with minimodem, but found the following eventually worked: minimodem -a --rx rtty --stopbits 1 -f new1ch.wav which produces output like ### CARRIER 45.45 @ 740.0 Hz ### SET YOUR ...
meuh's user avatar
  • 51.7k
3 votes
Accepted

SSH over incoming call from faxmodem possible?

There are getty implementations which support this directly, for example Mgetty (which should be available in your distribution). This will handle the modem on the server side, waiting for calls, ...
Stephen Kitt's user avatar
3 votes
Accepted

Linux ppp0 and default route and how to reach public internet

Facing a similar issue, sudo route add default ppp0 worked for me. If you need the process automated, you can create a script in /etc/ppp/ip-up.d, it will be executed when the connection is set.
Fred's user avatar
  • 46
2 votes

getting "bad init string" when dialing with wvdial

I experienced the same problem, then found that I did not have a SIM card in the device. When I added the SIM card, it worked again. Perhaps the SIM card is locked? I have seen other postings that ...
xirt's user avatar
  • 149
2 votes

How to send AT commands to a modem in Linux?

Try this: echo AT | socat - /dev/ttyUSB1,crnl This sends an AT command, returns the output and finally exits. The linux command can be used for several AT commands in script with a delay of 1 second ...
james.s's user avatar
  • 21
2 votes

List serial devices on FreeBSD

Use pstat(8). It will show you all the terminals, from which you can then subtract the virtual terminals (ttyv*) and ptys, leaving the serial ones - in this case ttyu0 and ttyu1, as documented in ...
Edward Tomasz Napierala's user avatar
2 votes

Is there a way to figure out a modem/router web IP address?

It's a little unclear what you want, but here goes: ping usually shows what ip it's using. That might be the address on your LAN side of the router, but that is most likely what you need. If you're ...
Henrik supports the community's user avatar
2 votes
Accepted

SFK to convert text to sound with minimodem?

A naive answer to this question is: cat example.txt | minimodem --write 1200 -f converted-example.wav After the generation, you may check with this command minimodem --read 1200 -f converted-...
Xiaofeng QU's user avatar
2 votes
Accepted

How do I configure APN settings on my QMI-based 4G modem?

So 4G/LTE modems provide a set of usb cdc emulated ethernet interfaces, including DHCP, and then provide a usbmic device for cell modem specific configuration activity, as well as the classic AT /...
Bryon Roché's user avatar
2 votes

Endless data loop from dev/ttyUSB while sending AT commands

Use "ATE0" Before echo "ATE0" > /dev/ttyUSB0
Irakli Khokhiashvili's user avatar
2 votes
Accepted

Data and control channels for a modem in Linux?

Devices which use the AT-style modem “interface” operate in a number of states: command mode dialing mode handshake mode data mode Modems start in command mode, and respond to AT-prefixed commands. ...
Stephen Kitt's user avatar
2 votes

How do I make ppp reliable over lossy radio modems using pppd and tcp kernel settings on debian?

As a partial answer to my own question, I have made significant reliability improvements through the following: Changing the tcp_congestion_control kernel plugin from the default cubic to bbr has ...
BrendanMcL's user avatar
2 votes
Accepted

Internet via audio?

You should be able to do it with SLIP. Check out this project log from someone doing exactly that: https://xenoworld.de/knowledge/slip.html
Kreshk's user avatar
  • 36
2 votes

Using Modem in Linux Mint

It's a 3-in-1 device that can work as: A 4G USB dongle connected to a PC or laptop A 4G USB WiFi cellular router/hotspot, USB flash drive when adding a MicroSD card. For the first feature, you will ...
jcbermu's user avatar
  • 4,756
1 vote

cannot access USB device from a program started with systemd

This is nothing to do with systemd or systemctl and everything to do with basic correct use of the chat program. chat is a program usually bundled with the PPP dæmon, and this has been answered ...
JdeBP's user avatar
  • 69.2k
1 vote

"Level 2 halted" error message using ldattach with mux type GSM0710

Did you issue a command like AT+CMUX=0 to the modem to trigger the mux in the first place? The mux stuff isn't working, that's why you're getting that error message. The kernel driver and AT command ...
dashxdr's user avatar
  • 11

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