Linux USB modem SMS alerts - linux

Trying to develop application using USB modem on Linux. Using Huawei E220 with CNMI=1,1,0,1,0 setup (also tried other CNMI settings none worked) and getting New Message Indications on received message to serial also on received Status delivery message. Is there any other way how to configure the device to enable received SMS alerts ? thanks Under windows machine it is working with no problems. The only problem is linux. Thank you

After a lot of testing and trying to install many linux Mobile Partner drivers finally I came up with an idea to try communication with the modem on different serial port. Linux mounts 3 different serial devices when modem is connected and as i was comparing the modem behaviour on linux to windows i had to connect to the third mounted serial port. I absolutely do not understand why the modem is accessible on two different serial ports but i found out that only one of them can write triggers to serial console. So in case somebody would have the same problem as i had the solution is to test all available serial ports in my case it was /dev/ttyUSB2.

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How to allow only 1 connection to BlueZ GATT server at any given moment?

I'm working on Bluetooth on the embedded Linux. I'm using BlueZ and D-Bus. I have a server taken from the example https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/test/example-gatt-server.
I have the app such as nRF installed in 2 iPhones. I'm able to connect to my Linux Bluetooth server at the same time. I'm able to modify the characteristic from either of the iPhone app. But this is a problem because we don't want it. We'd like to have only 1 phone connected to the Linux device. That way, the same characteristic won't be modified by more than 1 phone app at the same time.
Is there a way to allow only 1 connection to the Linux Bluetooth GATT server at any given time?
Thanks.
Yes, the way to do this is to disable/stop advertisements on your Linux device as soon as a connection is established. This way, upon a connection, your Linux device will no longer be advertising and remote devices will no longer be able to connect to it.

How to p2p_connect to device with WiFi Direct without MAC Address? (Raspberry Pi and Android)

I have an Android tablet and A Raspberry Pi and I want to established a connection between them automatically when the tablet sends a request to the Pi.
I followed an Android application example here and start discovering any nearby devices. (https://www.youtube.com/watch?v=qnY97iBxp30)
At the same time i run sudo wpa_cli and p2p_find 20. The Android application detects the Pi, and I try to establish connection with the Pi which will display
<3>P2P-GO-NEG-REQUEST TABLET_MAC_ADDRESS dev_passwd_id=4
Normally I would just p2p_connect TABLET_MAC_ADDRESS pbc to successfully connect them together but I find it inefficient if I were to swap to another mobile device.
Are there any other ways to connect the tablet without writing the tablet mac address? For example connecting to that specific device ssid when they send a P2P-GO-NEG-REQUEST to the pi?
TL;DR Nope.
If we look at the OSI ISO 7 layer model for network communication we can see that the Media Access Control (MAC) address is vital for identifying which device is which within a wifi network.
You could try setting up a bluetooth connection or a token-ring, but I suspect that would be more effort than you are looking for.
With IPv6 your devices could use neighbour discovery to automate past the MAC entry to the Internet Protocol, and its possible to connect between devices using their link-local address (fe80::some:thing)
Wifi carries packets of data, that have addresses. By analogy, if I tell you which town I live in, but don't write my building address on the packet, you are going to have a hard time delivering it.

Use a Linux Computer as a USB Coupler

I am on debian and:
I have a USB controller hooked up to a USB port on my PC (Device 1).
I have a male to male USB cord hooked up to another port on the PC that connects to Device 2. (it is a "bridging" usb cord, and has the chip for it)
I want to make them connect to each other as if they were one cord, so neither device knows that there is a computer in the middle.
This would be called a 'Coupler', except that I am using a PC as a coupler.
Here is a (really bad) diagram I made:
What I have done:
I have been able to connect the two devices independently of each other and sniff the results for when they fail to connect. The devices don't send a large volume of data back and forth.
Maybe there is some kind of command tool that I could use, for example (psudocode):
$ couple-usb-ports PORT1 PORT2
You're trying to reinvent the wheel here.
You might consider looking at this link instead.
http://dan3lmi.blogspot.com/2012/10/sniffing-usb-traffic-different.html
Specifically this.
Windows: You cannot directly capture raw USB traffic on Windows with Wireshark/WinPcap, but it is possible to capture and debug USB traffic on a virtual Windows machine under Oracle Virtual Box.
You cannot use a simple PC as transparent USB sniffer without extra (expensive) hardware. An USB bus has always one host (and one or more devices), and the PC can only be the host. This is a hardware limitation.
But you can capture USB data in a Windows machine using Wireshark and USBPcap, eliminating the need for the middle box in most cases.
As this post is tagged Linux, I suppose the controller PC is a Linux machine. Instead of connecting USB ports with a male-male connector, which is all kinds of bad (you are connecting the 5V lines of both machine with each other!), just run Wireshark in the controller PC.
There might be a little work to be done previously, as you have to enable Wireshark for USB monitoring (Particularly in Debian, this is disabled by default), and you might have to install a small driver to enable the monitoring. Have a look at this page for more information.
Once you get it working, Wireshark is an excellent tool for this!

How to connect to Bluetooth OBD II with visual C++ and for PC

I'm trying to use a Bluetooth OBDII (on-board diagnosis) to connect with a Bluetooth dongle connected to my computer (My OS is windows 7). The dongle connects to the device and assigns it 2 virtual com ports (COM4 for incoming and COM5 for outgoing), But unfortunately I couldn't communicate with this device over the virtual com port. I also attempted to work with winsock library but I didn't find any example for working with Bluetooth OBD and send and receive the instruments. I just found one Bluetooth API for android but it's not useful for me because I want to implement it inside the visual C++ and for PC. and right now I have 2 questions about that :
1. which method is better, Virtual com port or winsock and how ?
2. Do you have any sample code for working with Bluetooth OBD ?
1: Has your device a ELM327 chip? If so, you can setup a serial port over bluetooth, and communicate with that port. I don't know winsock very much, but I think a serial port is better suited for this job.
To set it up, have a look here: http://windows.microsoft.com/en-us/windows7/choose-a-com-port-for-a-bluetooth-enabled-device
Maybe if you can pair with the device, windows 7 will automagically set it up?
2:
You might want to have a look at: http://icculus.org/obdgpslogger/
It's open-source, so you can have a peek how it works. There's also a simulator in the package, which could help you developing/testing. Mostly is Linux based, but it should give you hints where to go. There are also windows installers available for the simulator.

How can I figure out which tty file points to which USB-to-Serial device?

I have two legacy machines connected to a Linux box with USB using the ftdi_sio driver, to /dev/ttyUSB0 and /dev/ttyUSB1. The Linux box is relaying and analyzing the traffic between the machines. When the Linux box boots up, the machines are connected to the files pretty much randomly. The problem is to know which one is which.
I could just ask the devices, of course, but I'd like to avoid the risk of malfunction due to sending wrong data to the wrong device. Is there a way to figure out, for example, the id of the device connected to a tty file?
Check this Using Linux USB page.
/proc/bus/usb/devices lists information about the devices currently attached to the USB bus. This is very useful when trying to figure out if the device is correctly enumerated.
Maybe you can use the output from lsusb -v and look at iProduct + iSerial to determine the order the devices are attached.

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