Force connection on specific USB port/symlink - c

I am planning to use Dump1090 and I want to have 2 RTLSDR dongles on the same computer, always plugged into the same USB port. I am planning to assign a symlink "adsb" to the port for the RTL dongle that has an ADS-B antenna connected to it. Is there a way to force the connection on this specific USB port?
By default, the code takes the first device available.
Thank you
https://github.com/antirez/dump1090/blob/master/dump1090.c

Related

Microcontroller not recognized at USB port when connected via pins

Im having issues with my TI LAUNCHXL-F28379D. I have it connected to the laptop I am trying to send data to/from via pins P19 (SCIBRxD) and P18 (SCIBTxD), as well as GND and 5V via J16, using a USB Type B cord to which I sautered pin connectors. I'm sure power is being supplied to the board as when I plug the 5V cable of the USB cable, the RGB lights and 3 other small ones turn on. However, the Computer does not recognize ithe controller at the port - it only recognizes if if it is connected via the board's Mini-USB port. I've also written a C Program which opens the COM port and reads data - but this does not work without my knowledge of the COM port number, usually found in Device Manager. I cannot get any further in my project without the port number and it is very annoying. I will attempt to resauter a new USB cable, but if there are any other possible solutions, or if I'm doing something wrong, please let me know.
Absolutely all feedback is appreciated!
The SCIBRxD and SCIBTxD pins belong to the SCI peripheral in the microcontroller. This peripheral implements a UART port (a.k.a. COM port, a.k.a. TTL serial port). It is not a USB port. Nothing useful will happen if you connect it to a USB port, because it is not compatible with USB in any way.
USB-to-UART adapters (a.k.a. USB-to-serial adapters) do exist. There is one built into the LaunchPad. The UART side of the adapter is connected to the SCIB pins, and the USB side of the adapter is connected to the USB port.

BLE Bridge Mode in Linux example

I want to use Bluetooth(4.0) on my board to transmit it's Name so any Mobile Application can see it's name and Mobile application initiates the pairing and connection with my Bluetooth.
I have seen some examples of Bluetooth(4.0) scanning nearby devices; For example:- It does scan for Bluetooth Mouser/Keyboard, but in this case Bluetooth(4.0) is in mode where it chooses the device it want to connect while I want it reverse so Any mobile application can see my Bluetooth and gets connect with it and does communication.
How can I put my Bluetooth(4.0) in such mode in Linux? Is there any C library using which I can put Bluetooth(4.0) is the mode where it goes in Bridge mode instead of scanning nearby devices?
You can set the name of your device like this:
hciconfig name "foo"
and check your name with:
hciconfig name
You also have to enable Low Energy advertising for your device to be found by others:
hciconfig leadv
You can configure your device to accept incoming connections like this (lm for link mode):
hciconfig lm MASTER,ACCEPT
This way the kernel will accept a connection, even if there are no listening sockets.
Considering you want to do actual communication, you would need to write a program, accepting the connection and sending/receiving data. Just putting your device in a mode where other devices can connect to it isn't really worth anything (because you can't communicate).
The basic principle is to open up an L2CAP socket, with the Channel ID of 4 (for Low Energy), then do standard bind/listen/accept. I suggest you look at the source code of Bluez and the examples.

Linux Serial Device Server over USB?

I have an embedded Linux solution and want to create a command service over serial USB. The idea being that when a computer connects to my embedded via USB, they see a serial device and send serial commands to me through that port and I send responses back.
I need some help in the direction to proceed. Do I need to emulate a serial device so they see me as a COM port? Is there build in Linux solutions to broadcast my details as a serial device? Are there code examples? I can see block devices connect with my embedded solution like a USB storage device. When I plug into another computer, I would like it to see me as a serial COM port.
I just need help in the direction of which path I should go down to solve this.
Thanks in advance.
What you are looking for is the Linux USB serial gadget. The Linux USB gadgets framework allows devices to behave as a variety of standard USB devices, including serial devices, Ethernet adapters, and mass storage devices.
Note that USB gadgets will only work on targets with a USB controller that can be set to operate as a USB device. Not all USB controllers and target devices are compatible with this configuration. For instance, most PCs have a host-only USB controller, and the Raspberry Pi Model B is not compatible with gadgets because it contains an embedded USB hub upstream of the USB ports. (However, the Pi Zero is fully compatible with gadgets.)

listening to communication between a local application and a device

I have a windows application on my PC which connects to a device over telnet. It sends a series of commands to the device, and the device responds to it.
Is there any way I can listen to what that program is writing to the device?
I tried using win32 socket programming to create a client that connects to the application. But, I get an error saying connection refused. When I analyze the traffic between the application and device on wireshark, I can see that the application uses different ports each time it reads from or writes to the telnet port(23) of the device.
Is there any way I can read the commands sent by the program to the device?
If you want to capture program's output to the device
programmatically, the right way is not to connect to the program (you
can't tap into an existing connection), but instead provide a server
that will stand for target device from the program's point of view.
It's going to work if the program can be configured to connect to the
device at different address and port. Write a "proxy" that listens on
some fixed port, and for any accepted connection, opens a client
connection to the real device. Then it should forward data in both
directions between the accepted connection from the program and the
client connection to the device. During this, you can also parse data
or do whatever you want with them, e.g. forward them to yet another
connection to another real device.

Activate and deactivate usb device in c?

We have a laser scanner which is connected all the time to a certain usb port.
The usb device should be deactivated normally.
Only at certain times I have to activate this usb device at the usb port with a litte c program.
So how can I activate a deactivated usb device in c?
Thanks for your information.
Update:
I forgot to mention to operating system: Windows XP, Windows Vista, Windows 7, ...
The laser scanner is a Honeywell Voyager MS 9540 product.
In the documentation I read that if the usb scanner is connected to a serial port, you can send enable and disable commands over the serial port in order to enable or disable scanning. But I thought it would be easier to simply enable or disable a usb port/device.
I bit more information would be useful ...
For usb connection you can use libusb (see also: libusb-win32). Since it's used by CUPS (a printing software) too, i guess its ideal for you.

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