I'm trying to get information about available serial ports in Rust to determine which one I'm interested in to send data using the serialport crate.
By doing:
serialport::available_ports();
I should able to get a list of available port. When I run the program as root (to avoid PermissionDenied error) the only result I'm getting is
SerialPortInfo { port_name: "/dev/ttyS0", port_type: "Unknown" }
I tried to remove all USB devices and ran the program but the result is the same. So I guess /dev/ttyS0 is an USB Hub but it is weird because it does not show me my USB stick, the keyboard, my mouse or my webcam.
I tried to open every /dev/ttyS{number} but the only one opening is /dev/ttyS0.
Here's my Cargo.toml file:
libudev = "0.3.0"
libudev-sys = "0.1.4"
serialport = { version = "4.1.0", default-features = true }
serial = "0.4.0"
I'm on Arch Linux and the program needs to be run on Linux. I installed the pkg-config dependency on the system and have udev too
Despite being the "Universal Serial Bus", devices on the USB are not recognized as being connected via serial ports. Actually, electrically it is not even a bus.
Only devices providing legacy serial transport like RS232 or RS485 fall in this category, commonly known as "COM ports".
There are serial ports connected via USB, though. These "virtual serial COM devices" commonly have the USB device type CDC/ACM and will be reported as /dev/ttyACM{number}.
Final line: You cannot access USB devices via serial ports, with the exception of virtual serial COM devices.
Related
What I want to do:
An AI program on a host machine, reading inputs from a camera sensing the screen of the target machine and outputting controls to the target machine via USB connection--programming the host machine's USB host as a USB peripheral connected to the target machine.
What I want to do step by step: (is it possible to implement the steps below?)
Have a host machine A and a target machine B.
Connect A and B with a USB 3.0 Type-A male-male cable.
The USB connection shows up as an HID keyboard device on B.
Write code to simulate key presses on A that sends to B.
(Eg. calling press('F') on a program running on A would type F to B's input)
It shouldn't require any program installed on B.
What I already searched:
USB 3.0 Host to host connection is possible:
https://superuser.com/questions/795053/how-do-i-connect-two-computers-using-usb-3-0
USB 2.0 Host to host connection is impossible:
https://superuser.com/questions/99274/how-to-connect-two-computers-with-usb
Similar questions asked without the assumption that USB 3.0 Host to Host connection is possible:
https://superuser.com/questions/1128365/simulate-usb-keyboard-from-machine
Setting up a computer to act as an HID device connected to another computer via ps/2,usb or another wired connection
https://superuser.com/questions/507921/computer-to-act-as-keyboard?rq=1
Suggestions in ascending order of feasibility:
USB Gadgets
You are using linux, so the default way would be to create/configure/load a gadget driver. Have a look at this tutorial, though for a raspberry, should work on your PC too. However, I could not find any information regarding the use of USB3 - the tutorial assumes your host is using one of it's OTG ports, which your PC most likely does not have. So whether this works with your USB3.1 Type-A-to-Type-A connection you'll need to test.
USBIP
The idea of sharing USB devices (not just keyboards) is not really new. With USBIP you can "export" any local USB device to the network, and your client will need the client-side USBIP driver to access the keyboard.
Dont bother with USB at all, just use Ethernet
I'd simply write two userland scripts/programs that send/receive+execute the keystrokes. Very easy to implement, you're probably familiar with python anyway.
If you absolutely cant have software installed on the client-PC and your Type-C-to-Type-C connection doesnt support USB Gadgets, there's another way. It basically involves the use of two USB-to-serial adapters (~15$) and a serial cable. While this wont be enumerated as a keyboard, but rather as serial port, it's the lowest-effort solution to transfer data without additional software on the client. Both computers will just do file I/O. If your computers still have COM-ports, you can even omit the serial converters!
I have hardware which is connected to the mac or windows via USB Serial Mode. Currently, I have a nodejs application which sends and receive messages to this hardware using "serial" node module.
I am trying to connect to the hardware from WebPage. I used WebUSB serial.js. I am able to see the device and guess it is connecting. But when I try to send/receive the message - it says unable to claim the interface.
I would like to know can I use the WebUSB for USB with serial support?
The claimInterface() call is failing because your operating system has already loaded the USB serial class driver for this device (or perhaps a vendor-specific one such as FTDI). USB interfaces can only be claimed by one thing at a time. The option to change the device firmware so that the interface is no longer recognized by the driver (modify the interface class or product IDs) then you will be able to claim the interface and use code like the Arduino WebUSB library's serial.js that you found.
The other option is to wait for Chrome to finish implementing the Serial API. Status on that can be tracked here.
What worked for me was to run sudo modprobe -r ftdi_sio in the console.
That way, it unloads the USB from the OS and makes it available for WebUSB to use it and claim the interface.
I'm hoping to use the newly released WebUSB API to communicate with a device i developed. This devices uses a FT230X USB to serial chip. The drivers of this chip are installed on most devices and communicating with it using minicom works smoothly. Now i want to try communicate with it through the browser. I started by downloading this example for arduino: webusb arduino. I set the filter to { 'vendorId': 0x0403, 'productId': 0x6015 } which shows the device. I'm able to find the device but when i try to connect i get the error: NotFoundError: Device unavailable.
Is there a way to find more specific errors? Should i set up a different interface or do i need to change some other configurations? I'm new to USB drivers so any help getting me on my way would be nice. I did read the (short) getting started documentation here. I use Ubuntu 16.04
The FT230X USB to serial chip does not provide an USB interface that Chrome can take control of. This is because, as you mention, the drivers for this chip are available with your operating system. With the serial driver attached Chrome cannot make the device available to your page through the WebUSB API.
The Arduino example programs the Atmel 32u4 chip on many Arduino and Arduino-compatible boards to add an additional USB interface which is not claimed by any system driver and is therefore available to Chrome.
Some developers have also had success either changing the vendor and product ID of their device so that the OS drivers do not claim it or by manually unbinding the driver.
I have a USB to RS232 adapter which I'm currently using to communicate with a legacy device. I want to analyze the data going to and from the legacy device from my Ubuntu machine over USB. The adapter is getting detected automatically without installing any driver as shown in lsusb output below:
Bus 006 Device 002: ID 0403:6001 Future Technology Devices International, Ltd FT232 USB-Serial (UART) IC
I tried using the USB packet capture in Wireshark, but it shows a bunch of URB_CONTROL, URB_BULK packets which is not showing anything meaningful. So if there are any better utilities available which can capture the USB2Serial data for a Linux system, please let me know. TIA!
After trying various methods, I finally got what I needed using strace. The following command helped me capture all the termios settings for the serial port and also all the IOCTL calls after doing some greps on the file handle of the serial port:
sudo strace -p <pid> -t -v -o dump.txt
This will dump all the system calls that your application makes on Linux into the file dump.txt.
I'm using node-serialport to work with USB devices, however on Windows I can't find out how can I connect to specific device. When I use list function there is only one item with COM3 address, however that is present always, even when no other devices are connected. How can I find out what is the USB device address that can be used for setting up communication?