I'm currently working on a device which is able to work as a keyboard and communicate via Serial with a self-written software.
Now I have to install serial drivers (from Arduino) on different computers if I want to communicate with my application which I actually want to avoid.
Is there any other solution to solve this problem? Is it possible that my microcontroller works as a keyboard AND is able to send and receive data as HID device?
Thanks and greetings!
I actually do something similar with a 32u4, but it receives its serial over the built-in UART. I do this because it's linking between two separate systems. If it were only one system I could implement a 2nd interface. (Don't forget, a USB HID device must have an IN endpoint even if you are not using it.) Or you could just throw a $2 USB/TTL converter on and do it the same as I did.
Related
I use the BLED112 and want to make it act like a HID keyboard.
The BLED112 receives the keystroke from the Mobile. For example, "p".
Then the dongle act like a keyboard so we can see the "p" is written on Notepad of PC.
Sending data from Mobile to dongle is not matter. I have already done.
My problem is to send the keystroke event to the PC so the dongle works like a keyboard.
I want an example or the full guide.
Thanks.
BLED112 is a Bluetooth Low Energy dongle provided by Bluegiga (Now acquired by Silicon labs). If you have studied the BLED112 user manual and bluegiga API reference documents, you'd understand that there can be two possible ways to read/write data via BLED112:
Use bgscript
use the bglib library into your C/C++ application
BLED112 is enumerated as a virual com port. I don't recall the name of the windows application that comes with BLED112 but it sounded like BLEGUI or something. This application uses the APIs to handle connections, read and write events. In a nutshell, you need to implement the same thing that this application does. For that, you can leverage the logs it spits on the console. This log will help you with all the commands you need to send and all the response that you need to handle.
Then, you need to make your application communicate with the virtual com port over which these commands will be send and responses will be received at.
Once you establish this, you'd be able to display your keystrokes.
It is a substantial work if you haven't worked with BLE. But like people say, there aren't free lunches!
I wonder whether it is possible to emulate a specific bluetooth device like a Remote Controller for a TV or another device with my PC. I'd be okay with installing an additional hardware device for my computer (e. g. a BlueTooth PCIe card).
I imagined something like "recording" all single commands of my original remote controller using my Bluetooth card and afterwards use these recorded commands to turn on my TV for example.
Is something like this possible (with additional hardware maybe)?
Of course this is possible. Bluetooth is just a protocol and you can impliment it in your custom software to emulate all kinds of devices. If you need to emulate simple devices like keyboard or mouse, there are many ready solutions like this.
But if you have non standard device, there won't be any ready solutions and you will have to implement it yourself. What can help you:
If you have some kind of controller for PC and you want to emulate device with unknown protocol, you can use WireShark or other sniffer to understand what's going on.
There is an emulator called BT-Sim, but it is so poorly documented that I can't even guess what it does.
You can can take as example different android software like described in answers to this question.
You can check different program samples for PC like this.
For hardware you need only simple Bluetooth dongle. However, if you want to spy on some BLE (Bluetooth Low Energy) devices, you can buy hardware sniffer like this.
(At least in Windows 10) Microsoft Store has an application called "Bluetooth LE Explorer" which is able to simulate different kind of Bluetooth GATT profiles as a peripheral.
I'm working on a little Arduino project to create a bluetooth N64 joystick for my Ubuntu box.
I managed to find a sketch to output the controllers state via serial and it works great. Also sending the TX and RX to the little CSR bluetooth module I have works fine.
When I pair with the device I have to use "rfcomm bind" to see the device in my dev directory and 'cat'ing the output shows all the data is coming through as well.
My question is this, what are my next steps for getting Linux to recognize this device as a joystick - i.e. /dev/js0. If I know what I need to do to achieve this I can read up on the necessary steps but at the moment I have absolutely no clue where to start - having not done anything like this in the past. Should I be looking into creating a Kernel Module?
Any information or pokes in the right direction at all would be greatly appreciated - even if it's just an observation.
Writing custom kernel code is definitely not the way to go here.
To make your project appear as a joystick device in Linux you'll want to present it using the Bluetooth HID profile. With that in place everything should "just work" on the client side and you'll see an entry in /dev. The HID profile is pretty comprehensive and is used by most Bluetooth interface devices - keyboards, mice, game controllers etc. the Bluetooth part of this is actually mostly just a thin wrapper around the USB HID protocol.
From the sounds of things your device is currently not advertising itself using that profile.
I have to simulate a USB Device for automation and testing purposes (in Linux). Original driver/application for this device uses “libusb” to communicate with it.
I don’t have much experience in Linux and Simulation, after some searching I have understood that I need to write a kernel level driver and an application in user-space to simulate that device. Is this right? If Yes, How can this be done?
Thanks in Advance.
Finally implemented it by modifying "libusb", modified it to send and receive usb transfers from message queue instead of usbfs. Programmed my simulator to create libsub type transfers and send/receive them using message queues as well.
Simulator now interprets the incoming transfers and sends it to a command parser, which sends request/message to automation system using sockets in a specific format. Automation system sends it's instruction by sending to command parser using socket. This socket invokes method specific to each request in simulator, Now simulator forms an appropriate transfer structure and passes to device plugin (via libusb) through message queue.
I think what you're looking for would be called a virtual USB device. Currently there is nothing in standard Kernel.Some virtual machine provides USB emulation.e.g. KVM provides USB emulation. There is framework gadget in which might look for your solution.
Or find something in Linux USB project
Thanks,
Abhijeet
The usb-vhci project could be of use if you want the device to be presented to the kernel in the same way as real hardware.
Is there a way to use one computer to send keystrokes to another by usb ?
What i'm looking to do is to capture the usb signal used by a keyboard (with USBTrace for example) and use it with PC-1 to send it to PC-2.
So that PC-2 reconize it as a regular keyboard input.
Some leads to do this would be very appreciated.
What you essentially need is a USB port on PC-1 that will act as a USB device for PC-2.
That is not possible for the vast majority of PC systems because USB is an asymmetric bus, with a host/device (or master/slave, if you wish) architecture. USB controllers (and their ports) on most PCs can only work in host mode and cannot simulate a device.
That is the reason that you cannot network computers through USB without a special cable with specialised electronics.
The only exception is if you somehow have a PC that supports the USB On-The-Go standard that allows for a USB port to act in both host and device mode. USB-OTG devices do exist, but they are usually embedded devices (smartphones etc). I don't know if there is a way to add a USB-OTG port to a commodity PC.
EDIT:
If you do not need a keyboard before the OS on PC-2 boots, you might be able to use a pair of USB Bluetooth dongles - one on each PC. You'd have to use specialised software on PC-1, but it is definitely possible - I've already seen a possible implementation on Linux, and I am reasonably certain that there must be one for Windows. You will also need Bluetooth HID drivers on PC-2, if they are not already installed.
On a different note, have you considered a purely software/network solution such as TightVNC?
There is a solution:
https://github.com/Flowm/etherkey
This uses a network connection from your computer to the raspi which is connected to a teensy (usb developer board) to send the key strokes.
This solution is not an out-of-the-box product. The required skill is similar to programming some other devices like arduino. But it's a complete and working setup.
The cheapest options are commercial microcontrollers (eg arduino platform, pic, etc) or ready built usb keyboard controllers (eg i-pac, arcade controllers,etc)
SEARCH THIS PROGRAM:
TWedge: Keyboard Wedge Software (RS232, Serial, TCP, Bluetooth)
then, MAKE YOUR OWN CONNECTION CABLE WITH:
(usb <-> rs232) + (NULL MODEM) + (rs232 <-> usb)
Connect 2 computer, write your own program to send signal to your (usb <-> rs232) unit, then you can control another computer under the help of TWedge.
The above mentionned https://github.com/Flowm/etherkey is one way. The keyboard is emulated from an rPi, but the principle can be used from PC to PC (or Mac to Whatever). The core answer to your question is to use an OTG-capable chip, and then you control this chip via a USB-serial adapter.
https://euer.krebsco.de/a-software-kvm-switch.html
uses a very similar method, using an Arduino instead of the Teensy.
The generic answer is: you need an OTG capable, or slave capable device: Arduino, Teensy, Pi 0 (either from Rapberry or Orange brands, both work; only the ZERO models are OTG capable), or, an rPi-A with heavy customisation (since it does not include USB hub, it can theoretically be converted into a slave; never found any public tutorial to do it), or any smartphone (Samsung, Nokia, HTC, Oukitel ... most smartphones are OTG capable). If you go for a Pi or a phone, then, you want to dig around USB Gadget. Cheaper solutions (Arduino/Teensy) need custom firmware.