Plugable

Howto: DisplayLink USB Single Monitor on Linux

Posted on 23. Dec, 2011 by jerome in Using

Unfortunately, Linux doesn’t support multiple graphics adapters the way Windows does, which means you can’t just plug in USB graphics adapters and expect them to extend your desktop (the good news is there is progress on this support).

What is possible, however, is running a single DisplayLink adapter, or several with a Xinerama or multiseat configuration — just as long as you don’t expect to use your main GPU at the same time.

The single-display case is relatively easy to set up, and we’ll cover that here.

First, make sure you’re running kernel version 2.6.35 or later (Ubuntu 10.10 or later). For older kernel versions, you’ll need to update udlfb and run a modified fbdev X server (not covered in this post). On these kernel versions, when you plug in your DisplayLink-based USB graphics device, you should get a green screen. This means that at the driver built into the Linux kernel is happy, healthy, and talking to the device.

Second, if you are running Unity Desktop in Ubuntu 11.04 or later, you’ll need to switch back to Classic Mode so you’re running straight X. Here’s how on Ubuntu:

Click on the power button in the upper right corner (mine looks like a light switch) and choose the last option, System Settings. Search for Login Screen, Double-click to display, Choose Unlock and enter your password, Select Ubuntu Classic as default session.

Third, if you’re running kernel versions between 2.6.35 to 3.1, enable the fb_defio option of udlfb. To do this, create or edit a file like
/etc/modprobe.d/50-displaylink.conf

and add the single line

options udlfb fb_defio=1

And reboot (or run “sudo depmod -a” and unplug/replug your adapter). This will turn on defio (page fault change detection) support. This option is already enabled by default in kernels 3.2+.

Lastly, create an X config file called 60-plugable.conf (or similar) with the following contents and place it in /usr/share/X11/xorg.conf.d (on recent distros; on older distros, make this your xorg.conf):

 
Section "Device" 
  Identifier "uga" 
  driver "fbdev" 
  Option "fbdev" "/dev/fb0" 
EndSection 
 
Section "Monitor" 
  Identifier "monitor" 
EndSection 
 
Section "Screen" 
  Identifier "screen" 
  Device "uga" 
  Monitor "monitor" 
EndSection 
 
Section "ServerLayout" 
  Identifier "default" 
  Screen 0 "screen" 0 0 
EndSection

Note: if your main GPU creates a /dev/fb0 even when the USB display is not attached, then your USB display is probably getting assigned to /dev/fb1. In that case, change /dev/fb0 in the “Device” section above to /dev/fb1

Now, on reboot, you should (hopefully!) see your login come up on your DisplayLink USB attached display!

This kind of simple setup is useful for:

• Testing or playing with your USB graphics adatper on Linux.
• Embedded systems with USB but no GPU.
• As a backup method when the main GPU or its driver isn’t available or working.
• Systems where a USB graphics adapter enables higher modes (up to 2048×1152) than the main GPU screen.

Please comment if you have any trouble with this single display case. See our past posts for additional information about the DisplayLink Linux kernel driver and some more involved setups.

The instructed here work on all Plugable USB 2.0 graphics adapters and Plugable USB 2.0 docking stations and thin clients (and should also generally work on all DisplayLink based products).

Plugable DC-125 USB Zero Clients Save Money for K-12

Posted on 28. Sep, 2011 by Bernie Thompson in Windows

One of our K-12 customers was kind enough to send “their story” of deploying Windows Multipoint Server 2011 with Plugable DC-125 Docking Clients, for this 2011-2012 school year.

It’s amazing how few people know about the possibilities of turning one computer into many with simple USB terminals. We’re hoping more stories like this will get the word out!

To Whom It May Concern:

I want to take a second and thank you for the support you have given me. It is not often I find such good people that take time out of their busy day to help! Thank you so much!

I voluntarily single handedly support a small non-profit K-12 school. A little IT history on that school was that as of early 2009, I started getting involved with the IT Infrastructure. In reviewing their systems, I noted that they were running a Microsoft Small Business Server 2000 to which was only used to serve IP address and keep some files in a fileshare. The server had been installed in 2000 to which had not been maintained since then except for the occasional reboot and update.

In 2009, Microsoft announced that they would discontinue the support of Microsoft Server 2000 in July. Knowing this, I began having meetings communicating to the staff of the impacts of running a server without having support for major things like updates. I helped them decide that we should upgrade the infrastructure to Microsoft Small Business Server 2008 as well as source a new server to run the software.

While the server was on order, we began updating the entire wiring infrastructure of the network cabling to consistently possess at least Cat 5 cable.

I installed the new server as well as setup the ability to use Microsoft Exchange Server, Sharepoint Server, and a file Server. Also, I made sure to install a raid system as well as a nightly backup system. For the first time, the staff had email addresses with the school name! The staff we all very excited to use the new system.

Noting that there were many old computers that were at least 7-10 yrs old, we sourced and installed Microsoft Server 2008 in a Hyper-V session in order to use Terminal Server, now called Remote Desktop Services. On that Terminal Server, I installed all of Microsoft Office 2010 as well as other pertinent programs needed for the school. This allowed a repurposing of all the older computers as well as combining the old computers with new flatscreen monitors. The speed of the Terminal Server made the staff feel like they all had brand new computers!

I had been using the Comcast Modem as a firewall and knew that the firewall needed to be upgraded. The school needed a way to track everyone on the internet as well as the capability to filter the internet. I sourced a smaller used HP DL380 server to run an all-encompassing web filter, spam filter, firewall, routing, etc., named Untangle. This also sped up the internet experience as Untangle has the ability to cache websites.

Next on the list was to revive a computer lab that had not been run in over 2 years. There were several questions to be answered in order to ascertain how the lab was going to be built with these criteria in mind:

· Cost Effective

· Ease of maintenance

· As Energy Efficient as Possible(green)

· Reliable

· Ease of use

With that in mind, we came up with a few options. The first option was to utilize the computers from the old lab with a Terminal Server session. Because the base software of the computers was Windows 2000, they would have to at least be upgraded to Windows XP for security and Microsoft support reasons. Because of the expense and support needed, we decided against doing that option. Specifically we did not meet the goals of:

· Ease of maintenance

· Reliable

· Ease of use

The next option was to utilize “nettop” computers, specifically the Foxconn NetBox-nT525 nt525-0H0W-B-A-NA-BOX that we could mount to the back of a monitor. We then sourced 10 refurbished Dell 19″ monitors. I purchase one of the mini computers for test. I installed both Linux Edubuntu as well as Windows 7. The problems with this route are that it did not meet our objectives because:

· Not as cost effective because of the need for 10 computers

· Increased maintenance need

· Having to learn Linux by the staff therefore not easy to use

· No ability to use Remote Desktop into the computers (would have had to install VNC)

The third option was to install a dumb terminal system. Two systems were looked at including Linux Userful and Microsoft Multipoint Server 2011.

I admit that I am not near as intelligent on Linux as I am Microsoft products. For Linux, I know just enough to get me into trouble I think. I can do almost anything I want with any Microsoft OS and almost all software. With Linux, I have to struggle and look up internet blogs to help me with basic functionality. This is the second main reason I chose Microsoft over Linux.

We ultimately chose Microsoft Multipoint Server 2011 and here is why: I guess I could really boil it down to be selfish. Because I need to be able to support the school, I want the capability to remotely connect to any user computer either interfaced with the user or totally without the user in order to solve issues. Also would like to remote to apply updates and normal/general server maintenance.

The server we purchased to run the environment was a Dell R210. It is a 2.93 ghz Xeon Hyperthreaded Quad Core with 16 gb 1333mhz ram. It should be able to do whatever we want in this situation, right? Wrong. I also sourced 5 DC-125 units from Plugable to test the server for the needs of the school.

I then installed Microsoft Multipoint onto the server as well as all the displaylink software required. I tried plugging in a DC-125 to which did not work as expected. I then began troubleshooting.

After 3 weeks of troubleshooting with Dell and Microsoft, I got nowhere near making the system run. I then began consulting with Plugable. They had absolutely phenomenal support. Very quickly we determined the situation was caused by the 1998 technology used by Dell for the video card.

I then sourced an ATI 2270 video card and placed it in the only open slot. It worked! Yeah! If it wasn’t for Plugable’s awesome support, I would have had a very expensive paperweight as well as the need to go out an purchase 10 computers with Operating Systems!

Let’s talk about GREEN! The lab is only running one computer instead of 11. The server is running an LED monitor which is 1/10th the power requirements of LCD. The ATI 2270 video card only uses max 17.5 watts of power. All combined, the lab requires very little power requirements than what would have been.

As for the rest of the criteria, it was all met.

So, this is where we stand in the school, an operating lab based on Microsoft Multipoint OS connected to Active Directory and the internet. Have tested the system with 2 workstations running full screen Hulu and one running full screen YouTube and the frame rates never dropped as well as sound/video never got out of sync. I am extremely happy with this setup!

About me, I am an “old” computer guy I guess. Sometimes I still prefer DOS over windows. My favorite computer language is Assembler. 95% of everything I have learned has been on my own eventhough I do have a degree in CIS. I don’t admit readily to others that I know anything but I normally get tasked to fix everyone’s computer. (I gotta stop doing that or at least charge.) In my home, I am running a full server with exchange, IIS (I can run Apache just fine), and other network technologies which is where I have learned the most and have been doing this for more than 10 yrs. My entire family, internal and extended, all syncs their phones to my exchange server for email, for free.

As you can see, I love computing platforms as well as the social aspect. I also love to be on the bleeding edge. Companies like Plugable really go the extra mile to help everyone, especially to support the needs of a non-profit school. I love Plugable and their DC-125!

How to change the COM port for a USB Serial adapter on Windows 7

Posted on 04. Jul, 2011 by Bernie Thompson in Windows

Start by going to the Device Manager. Once there do the following:
Expand the Ports ‘(COM& LPT)’

You should be looking at something like this:

As you can see Windows has set the port to COM10. However many legacy applications expect the port to be between 1-4. Let’s change that:
Right click on the device and click on ‘Properties’.

Click on ‘Port Settings’. Then click on ‘Advanced…’.

Once you’re in ‘Advanced Settings for COM10’ on the bottom you can see the ‘COM Port Number: COM10’. Click on that to change it to the lowest possible number (between 1-4).

Then click ‘OK’ on all open Property Windows.
Now the device should look like this: