I have a USB audio device (Scarlett Focusrite 18i6) which does not require a driver, so I assume it uses the USB HID Audio Class standard.
It works on everything from Windows and Mac to Linux and iOS.
But on Mac and Windows, it has a control application which can for instance enable and disable direct monitoring.
How would I go about reverse-engineering how this is done, so that I can reproduce it on platforms where the control application does not exist?
I'm thinking of booting up Windows in a VMWare session and then logging the USB communication (somehow?) while using the control application, but it does sound tedious considering the amount of data and my very limited understanding of USB.
Any other suggestions?
You could try running the control application using Wine instead of reverse engineering it. However, if it's accessing USB devices then there is a good chance it might be using an API not supported by Wine.
To reverse engineer it, you should find a way to look at the USB traffic between the computer and the device. Total Phase has some hardware USB protocol analyzers, but you might be able to find a good software solution for free.
Related
I have a WPF desktop application that would make a good candidate as a Universal Windows App. The application has a must-have dependence on USB or Bluetooth devices that act as a Serial Port.
In all my reading I've yet to discover whether there is any access to a SerialPort API in a UWA.
I suspect the answer is 'No support'. If so, does anyone know of a USB or Bluetooth GPS that supports whatever APIs the UWA has for that sort of thing. I have to be able to read things like ground speed, elevation, rate of climb, etc.
If the answer is 'Supported', could you point me to some documentation.
For the "Bluetooth devices that act as a Serial Port", I assume you mean the RFCOMM. They are both supported on Windows Runtime since Windows 8.1 and you can also use them in the Universal Windows Application.
namespace: Windows.Devices.Usb and Windows.Devices.Bluetooth.Rfcomm.
About the Bluetooth GPS, I'm not sure if it uses RFCOMM or not (it depends on the devices), and it is also possible to use the GATT.
Code Sample: Custom USB device access sample
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!
I'd like to redirect traffic from and to USB devices in an application.
Particularly I want to talk to USB dongles.
So for example if a dongle is connected on a USB port, is it possible to get the traffic that is intended to be written to this device? On the other hand, can you simply write data in the same manner?
I don't have any experience so I'd appreciate to get some directions.
BTW, this is not intended to be used in anything illegal ;-)
With "USB dongles" you mean: Software license dongles?
First of all you should know that USB is not a stream of data such as RS232 but a very complex bus transferring a lot of different control and data messages.
On Linux you can use Wireshark to monitor the data on the USB bus. There are similar tools for Windows (up to Windows XP only) but the Windows version of Wireshark does only support Ethernet and not USB. Windows 7 has a built-in command line tool that does the same job.
If you really want to redirect data you might use something like "usbip" that allows sharing USB ports over network. You may simulate an USB dongle device by programming a server that simulates the dongle... However doing this is very tricky and requires a lot of programming experience!
I have a USB to parallel port device that i want to interface with through c++ on a modern windows OS (xp and newer).
I've done a little research but the information is a bit patchy when it comes to programming to one of these USB to parallel port devices (most of the information is dated and assumes that you have a parallel port built right into the motherboard, something my brand new computer doesn't have). One reference even says that it is not possible to interface with a USB to parallel port from a C++ program without some sort of software changes.
All i want to do is to is be able to read or write 8 bits to the parallel port through a USB to parallel port device on a modern computer running a modern windows OS (with ports being dedicated to reading or writing only).
Is there any quick and easy way of doing this? Some sample code would be greatly appreciated.
Also, how many of these USB to parallel ports can I interface with my computer? Am i limited to 3 due to some sort of legacy addressing or can i have as many as my USB and CPU are able to support?
Working off VC++ 2008, running Windows 7 x64 with a Core i7 860.
Edit: a bit more information...
I've tried using inpout23 along with some prewritten test program. It compiled just fine and ran just fine claiming to have both read and written to a parallel port. I had my USB to parallel port connected to the computer and that port connected to a cable in which i had identified, stripped and soldered each of the 25 wires onto a sort of plug for quickly plugging into a breadboard for testing. None of the output pins had changed to what the program had said was written to them (instead they were all set to high and never changed).
I've done this in the past and I have good news and bad news.
The good news is that it always worked (sometimes with tweaking), which is a tribute to the electronic manufacturers of designing extremely robust protocols. Apparently the USB to parallel converters all provided the hardware port emulation.
The bad news is that performance was awful on the 'bitbanging' interface models. If you do not mind slow updates this is not an issue at all. I used it for programming uControllers and soon the price of serial or USB programmers was overcome by my impatience.
Just use the windows API to read/write the LPT or COM ports and it works (slowly).
I've worked with a USB-to-serial port adapter before and I guess USB-to-parallel should be the same. You should have got a driver along with the adapter - this does most of the work for you, hiding the USB interface and presenting it to the OS as a traditional parallel port. For example, when I plug my adapter into the USB port, it just shows up as COM4 in Device Manager. I'm guessing yours will show up as LPT1 or something. From there on, it's a matter of using the standard Windows API to access these ports. (see Communications Resources on MSDN)
Misteriously I succeed with the USB to LPT-DB25 Wire bought in ebay.com.
We should connect a LED between the /LF Line Feed and GND pins.
After discard the USB registers in order to find that one associated to the USB Cable, we should build an API (Application Programming Interface) to interact with the outputs/Registers.
I'm going to try to attach a picture to have a look how I managed it:
I am looking at integrating a C# application with a barcode scanner.
The last time I did this was with Delphi 1 (win 3.11) using a scanner that plugged in-line into the keyboard cable.
Looking around it appears most scanners are USB based these days and assume they emulate keyboard entry.
Anybody know of more sophisticated/programmable scanner that can call a webservice or even just do a basic POST/GET this would eliminate the C# application and the computer to support it?
There are a number of Ethernet and Wifi code readers on the market, though they tend to be targeted at industrial applications and usually cost more than the USB models. The company I work for makes such readers, and our fixed-mount DM200 reader is just such a device.
You could use a small computer (or even a microcontroller) with RO media, USB, and networking capabilities plus a psu to turn any suitable scanner to a network one. Raspberry Pi, for example, could do it and seems to be hip these days.
Alternatively some portable devices (like Android tablets) could probably use a camera or even a USB scanner for scanning codes and come with capable networking features.