Device Connections Problems

[Apple Tsai]

Hi Virtual Box Members:

Here is one problem that enocunter with using the virtual box machine software.

The problem is I used an USB Devices for doing some program downloaded. but I also wish to let the virtual box detected my devices.

I have tried several times of setting the USB devices and connect /disconnect the wireline connections.(as attached picture )

However, the virtual box can not detect the USB device .

Can anyone can tell me how to solve/improve this problem?

because this tool seems can detect sometimes!!!

[mpack]

Let's see if I understand this correctly: you are using a USB-RS232 interface (by FTDI) to communicate with a single board computer of some kind, but sometimes the guest fails to detect the USB device?

Using physical hardware is not really what VMs are good at. And I assume the baud rate is high and fixed in the board you're talking to, otherwise I would suggest using a virtual serial port and a lower baud rate.

I think you should configure a USB filter for the USB-RS232 device, and remember to always plug the device in after the guest OS has finished booting up. Still, I'm not highly confident that this will ever be reliable.

[Apple Tsai]

How to set up the lower baud rate and virtual serial port ?

[mpack]

Serial ports are configured in the VM settings. Typically you would map the host COM9 (or whatever) to the guests COM1. Baud rates are chosen by you and the two devices, it is not a VirtualBox configuration matter. Lower baud rates may be more reliable.

Remember not to access the device using both methods (serial and USB), as that will not end well.

[Apple Tsai]

In fact, I am not sure that I can fix this problem,
because I think it may not really due to the virtual box
but might mainly due to the linux operating system.
I used the lubuntu 16.04 version.
In the beginning, virtual box can detect the devices ,
but few times later, the virtual box can't
so do you suggest me to reinstall the operating system?
or use other suggested system ?

[mpack]

You need to tell me if you're using the USB method or the virtual serial method. In the latter method the serial ports should always be available to the VM, though Linux may insist that your user is the member of some group or another in order to get access. Reinstalling the guest OS should not be necessary.

[Apple Tsai]

please direct me a serial port method. Thanks you

[mpack]

I already told you about it two posts ago. It means to configure a virtual serial port in the VM settings, which ultimately uses a host serial port for physical I/O. The guest would not use USB in any way, and must not as that would kill the host port.