Logic Analyzers And X11


[Andrew] recently scored an awesome HP 1670A Deep Memory Logic Analyzer, lucky dog. Even though this machine was built in 1992, it was a top of the line device back in the day and had a few very interesting features. This logic analyzer also had a few networking ports implementing FTP, NFS, TCP/IP, and the X11 protocols over a 10Base2 (“thinlan”) and 10BaseT (“ethertwist” seriously, that’s what’s in the manual) connections. The X11 protocol interested [Andrew] so he set this logic analyzer up so he could use it via his Linux box.

X Windows is simply a way to display GUI interfaces over a network. While today we usually only see X Windows apps confined to the desktop, in the bad old days of *NIXes you had to pay for, running a GUI app over a network was considered the wave of the future. The Internet replaced this idea with a palimpsest of JavaScript, but we digress…

[Andrew]’s new toy didn’t support DHCP, so after inputting the IP address manually, he checked the host file – still the same after twenty years – and connected with his Linux Mint box. The result is a remote control panel for the ‘ol girl in a garish color scheme that violates all modern sensibilities.

18 thoughts on “Logic Analyzers And X11

        1. Yes. The application itself is running on the logic analyzer, and is the client.
          If you read the source article, you see that he’s actually exporting the X display from the client program on the login analyzer to the local X server on his Linux box.

          What’d be even *more* fun, is trying to set one of those up to talk to an HP Xserver terminal like a 700x or Envizex.
          Like one of these bad boys: http://www.kf5rsx.com/updated-hp-envizex-files/

    1. A “hack”? Fine, no. Amazingly useful feature in that logic analyzer? Heck yes, I’d love to be able to X-forward from the logic analyzer to my desktop.

      I can’t quite tell but it looks like they could be using the Xt bindings, so you might be able to use editres to change the colors.

    2. X11 is pretty much deprecated for everyone outside the linux scene, so resuscitating dead protocols is indeed a hack of sorts

      (X11 will be deprecated in linux too if canonical gets their way)

      and good riddance to it, what a nightmare X11 is.

      1. Not just Canonical, whilst they’re developing Mir as a replacement most of the rest of the Linux world is moving to Wayland.

        Wayland doesn’t (yet) support anything like X11 forwarding which is *incredibly* useful for my job. I deal with headless servers and some of the applications customers like to install either require a UI component or use a UI to make the installation process a billion times easier (not impossible without but it just takes so much longer). Yes we can use VNC and the like but X11 is generally smother, quicker and already installed so doesn’t need to undergo change requests for install. It’s not a useless, it’s rarely a nightmare (yes there are exceptions where it’s clear the spawn of the devil) it is in fact brilliant. If only it had been properly updated over time rather than left to fester with old technology littering the protocol standard

      1. Even if this isn’t a hack, it’s an awesome piece of equipment. Putting X11 on a lab instrument, so you can take advantage of the much bigger, better displays available elsewhere, even over a network, is quite a hack, well hacked, HP!

        Maybe Andrew or another owner would like to route it over the Internet? Connect it to an interesting circuit and let the public do some analyzing for a day or two? I’d find it interesting, and try my best not to break it.

  1. I usually NFS mount my HP 16500C and then download the recorded samples, since the HP logic analyzers are horribly slow in updating the screen, if deep sample modules are installed and all the memory is used (the 64/128k of the HP1671A isn’t exactly deep memory compared to the 2/4M of a 16556D card).

    The recorded samples are then converted to a GTKwave compatible format by the “la2vcd” program and viewed in GTKwave on a laptop

  2. I’ve got access to an HP 1661C which looks to be the same externally and does indeed support X11, it was a rather large nostalgia trip seeing the bright colours on my laptop.

    Unfortuantly I am missing the font used to render the keypad that appears when you try to enter values which causes the analyser to hard lock.

  3. This is exactly the sort of thing that makes X awesome! I really fear what is happening now with Wayland on the horizon. It would seem that the current generation of developers doesn’t understand or at least care what kind of things made some of us choose Li/Unix and X in the first place.

  4. “… While today we usually only see X Windows apps confined to the desktop…”

    I use remote X all the time! It’s how I get a graphical terminal to my main desktop which lives upstairs in the den down to my garage workshop. I just turn it on and there it is… a graphical desktop session just like if I was upstairs, I don’t have to mess around with connections, VNC or anything.

    I also use rootless windows from time to time, sometimes even away from home. It’s great to be able to put two programs side by side, one local, the other remote. I can even copy/paste back and forth, it’s like they are both running locally.

    How the heck does javascript replace any of that? I suppose if all you want is shared access to documents then the cloud is fine though only if you want to share all your stuff with Google/ etc… For something more interesting like remote displaying a logic analyzer what does Javascript have to do with anything?

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