Slashdot Mirror
Cheap Homemade X-Terminals?
aoechsli asks: "I am in the process of setting up a computer learning center for K - 12 age students. The system will be based on a network of about 10 - 15 X-terminals all running off of a server (duh). I will be running Red Hat with KDE2 (when it comes out). It will be used for office aps (Koffice) and Web browsing (Konquerer). What I need help with is trying to find an inexpensive set-up for the X-terminals. I have abandoned the donated hardware route as the set-up of each for individual machine proves to be overwhelming with my limited time constraints. I may be able to secure some funding, and if that comes through, I would like to use a standardized set-up with all of the terminals. I am looking for a small footprint, low power set-up. My proposed solution would be to make an X-terminal with a single board computer and a flat panel display (the 10" LCD seems adequate after seeing the I-Opener.) What flat panel displays are supported? I thought about using flash memory for the boot image, but thought that a smaller HD would be more appropriate. Does anyone have any suggestions on what would be optimal and inexpensive? I am looking to spend no more than $350 on each unit."
I would love to know of another source of 800x600 passive-matrix LCD screens, but as far as I can tell, laptops are it.
If you look around, you can find P90 laptops for around $400, not including network or CDROM.
Yes, but it may just be difficult, not impossible. I've seen someone running the Xggi server with the aalib ASCII art driver in a Linux console. The only problem is whether or not a VT100 can handle the screen updates fast enough. For a text terminal, though, they're great. I used to use one many years ago. Just connect it witha serial cable, spawn a getty to the right port and away you go.
"The invisible and the non-existent look very much alike." -- Delos B. McKown
Uhm... "geek", VT 100's are text only. So I'd venture to say that, no, no one has gone down that road before.
--
I think there is a world market for maybe five personal web logs.
Personnally, I would not use laptop for the following reasons :
I never completed a similar project, but I would definitely do it with second-hand PC if I had to. A nice place to buy older hardware is IT Xchange. They are a bit pricey, but the inventory is large. Personnally, I'll buy a batch of identical machine to ease maintenance. I'll definitely buy brand new monitor however (for picture quality and reliability).
Another option would be older Sun hardware (SS2, SS5). However, these suffer from some of the same problem as laptop (expensive part, price/performance ratio, etc.). But if you insist on exotic hardware, you could get these cheap on Ebay.
Have you given a tought about the network? X is a network hog, so it would be worth considering network capacity. IMHO, switched 10baseT sould be enough, and I'll choose that over shared 100baseT anytime.
Also, you should give the Linux based diskless X terminal toolkit a look.
Just my 2 bit ...
:wq
Don't be so quick to reject the "donated hardware" approach. An old Pentium PC with a default kernel and a $30 Tulip-based 10/100 managed NIC isn't going to need much special configuration. The XF86_SVGA package should be compatible at 800x600 or even 1024x768 on nearly any hardware you throw at it, even if it won't necessarily be "optimal".
Let's imagine you're using RedHat or Mandrake, for the sake of keeping this explanation simple, though similar things can be done with Debian-based distros, too. Once you've got the right assortment of packages loaded and have removed the ones you don't want, you can make a kickstart install floppy, which will allow for a hands-free install (put in floppy, put in CD, and power on).
If you're okay at making your own RPMs, you can make an extra RPM with your configs (for example, configuring the eth0 interface to configure itself via DHCP, and activating NIS or pam_ldap to participate in centralized configuration). Burn that onto your otherwise-ordinary CD.
With a bit of planning, unless you have some weird and eccentric systems in the mix, the only substantial thing you'll likely have to do manually is run Xconfigurator, since every monitor and video card dot-clock is possibly different.
The hell with KDE2 anbd KOffice. It's not going to be finished and stable for months, nice as it'll be. Same goes for GNOME, which is imprioving but just not stable enough yet. Go with KDE 1.1.2. It's extremely stable and a fairly seamless end-user environment. For office software, go with StarOffice 5.1a. It's cost-free, full-featured, easy to learn, and there are good books on it available at any bookstore.
The thing about this is that both KDE and StarOffice (or for that matter, Corel Office) are very resoure-hungry. You will need a server (or more than one server) with a whole lot of RAM (assume at least 32MB for each connected user) and, (guessing off the top of my head), 70-100MHz of processing power for each.
If you want to be able to scale down the server, you may want to look into a leaner (but less capable) desktop environment, and Applixware, which is a leaner (but not free) office suite.
Why do they need an entire office suite, anyway? Will something like LyX/KLyX for documents and Gnumeric for spreadsheets do what the kids need?
$350 with displays is really pushing things. It can be done, but isn't your time worth something? The iOpener is cheap not because a computer can be made for $99, but because it's being sold at a loss with the expectation of people paying for monthly service.
I actually recently came into ownership of an honest-to-goodness Digital VT 100 terminal. (stop drooling, geek!) and hope to set it up as an X-term for my home linux server (when I get that running, mind you). Anyone gone down that road before?
Returned Peace Corps IT Volunteer
Since they're just X-terminals, maybe you could get a bunch of identical, low end Pentium laptops, and bolt them down.
If you could get docking stations too, that would avoid the need for PCMCIA NICs.
An my list of things to do is to turn my Thinkpad 500 into an X-terminal.
George
But at the $350 price point, I don't think the LCD screens would be are available any other way. If you can use say a 15" CRT (looks OK at 1024x768)... Then you have lots of options for putting together standardized boxes with reasonable specs. You may want to look at the "Book PC" type machines discussed here earlier... The ones based on the i810 chipset are pretty well supported by linux (with the exception of the winmodem, which wouldn't be needed in your application anyway).
Good luck!
-MattT *** Not speaking for my employer, or any other sentient beings ***