• Please review our updated Terms and Rules here

Help me with my Data General terminal

Unless you can dig up some documentation or happen to find someone who know's these things well, it's difficult to help you fix this without seeing it.

That said, it would appear the problem is either the keyboard itself or the interface for this on the main board. If you're not able to test any of the parts, you're pretty much limited to visually checking components along these lines.

Maybe you should enlist the help of a professional technician? I know a few hang out here, but I'm not sure if there are any near you. What you'd need is somewhere that can do proper fault diagnosis and repair, as opposed to the board-swapping shops that are commonplace these days.
 
YAY! I don't how or why, but it works! Yesterday I was checking the resisters on the board, one or two of them were not to good but there were close. But then I
Pluged the keyboard in and NO MORE ZEROS! I quickly put the keyboard back together (fist taking off all the bad foil pieces). And somehow it works! I guess there was a cold solder on there somewhere that I missed before somehow. About half of the keys are working right now, and all the rest should be working soon. Now you're right, I need a Nova to go with it.:rolleyes: Btw, the scorch mark is right under the anode on the moniter tube, and from pictures I've seen of other ones, there should be a heat shield there.
Thanks everybody for your help and for looking for a manual. I found a website about someone who owns a Data General Nova and has this same terminal with it. I'll probably email him and see if he know how to get to the setup screen (if there is one on this terminal). I'll have a couple pictures of it working later today.
 
Thanks Pontus. Here is a picture, I might post some more but I have to figure how to make them smaller. Sorry it took so long, but I fixed the keys first. I used 3 layers of double sided mounting tape to replace the foam.
 

Attachments

  • P1040281.jpg
    P1040281.jpg
    92.4 KB · Views: 1
Kirbot said:
Thanks Pontus. Here is a picture, I might post some more but I have to figure how to make them smaller. Sorry it took so long, but I fixed the keys first. I used 3 layers of double sided mounting tape to replace the foam.
Click to expand...

Neat!. I also like the leather cover you have for your C128 (i think it's a C128)
 
Yup, It's a 128. Heres a picture of how I fixed the keys. I didn't remember to take any pictures when I was doing it but here you can see the three layers of tape and the sharpened pipe I used for cutting the tape, it took forever to do but it worked great.
BTW I posted a bunch of pictures in my album.
 

Attachments

  • foam.jpg
    foam.jpg
    56.4 KB · Views: 2
Last edited:
experiences with dumb terminals

experiences with dumb terminals

I love dumb terminals. Who doesn't?

I've had my share of 3 dumb terminals, and ran into a 4th one.

Unfortunately, they all did not have original keyboards.

Obviously, they had proprietary keyboards for themselves, because when I tinkered with the ones I had, using an IBM clone keyboard, they would not respond with characters I assumed it would.

Getting the serial protocol and speed it wanted was hit and miss as well.

I did get some weird characters eventually, and double characters meaning it was decoding both the keypress and release scan key codes I was feeding it.

Obviously this would've taken something more, like maybe a BASIC Stamp converter in between to change the scan codes into it's native tongue.

The 4th dumb terminal I found was a WYSE terminal at a junk store. If I get five bucks and it's still there in a few days I might pick it up, but it had a REALLY weird keyboard port. I think it was a DIN 8 or something connector, not a 5-pin DIN like the old XT keyboards. I would have a hard time getting that to work with anything without that keyboard language translator device.

I don't think I'll be getting it.

I did however, do some experiments using my DOS computer as a dumb terminal. I'm going to make some graphics editors that work with two computers at once like the old Lucas Arts setup was. Fancy hi-res terminal networked locally to a dumb terminal for mundane text rendering and menus.

People still use 2nd generic monochrome monitors for CAD drawing. I did in college for a class. It wasn't dumb terminal anything, but you get the point that they used the lower class tech for the generic crap to save screen area on the fancy one.



Congradulations on your terminal working. It looks very 70's-ish. You should find some amusing toy that emulates a ""SUPER HIGH NEW FANGLED program from that time, or something like Eliza hosted from another computer.



Kiyote!
 
Forgot something

Forgot something

When ever I start a new major project, I usually include code to emulate a standard ANSI window for displaying either amusing dated graphics and stuff, or as an easy way to add a console to output raw data to when debugging or editing script functions of stuff..

Blah blah blah..



Kiyote!

I keep thinking of Austin Powers and somebody behind the desk having one of your terminals now.. hahahha

P.S. I've seen dumb terminals (10 years ago) that had a current loop BNC type connector on it for connecting to the network (mainframe). Does anyone know how these type of connections work exactly and how to interface with something modern today? I assume it's probably a twisted pair type thing as RJ-45 works now, with a positive and negative swing, but I'd like some specifics. I don't wanna just guess and wonder for the rest of my retro-loving life.

Kthnx
 
Last edited:
Are you still looking for schematics?

I have a set for the main board, but not the keyboard.

I also have a user manual.

I can scan them, but it may take a few days. The keyboard is stupid simple...it's capacitive, scanned under control of the 6802 processor, which shifts a "1" into a shift register on the keyboard, then looks to see if a pulse comes out. The shift register connects to the [rows? columns?] and the sense register connects to the other. Pressing a key causes the metallized mylar on the foam to act as a capacitor connecting row and column. The ICs are all marked with DG's proprietary numbering scheme, but, for the most part, they're standard TTL and CMOS parts.

I worked on the design of the D100/D200, so I know lots about the digital side and not much about the analog side.
 
That VDG sticker on the back means the terminal was once DG property :)

The dark spot on the PCB under the CRT anode connection is probably just dust accumulation, attracted by static electricity from the anode cap. By the way...DO NOT TOUCH THAT ANODE CAP. If you need to remove it, use a long screwdriver, grounded to one of the "gold" spring wires that holds the upper half up. Slide the screwdriver under the rubber cap, until you hear a SNAP, then it's safe. Of course, you do all that ONLY after unplugging the terminal!

In retrospect, that was a very poor location for the high voltage anode cap...right above the sensitive logic board :)
 
The foil pads on the keys are *not* conducting...there's a thin insulating layer over the foil. They work by capacitively coupling a pulse from one half-moon pad to the adjacent one.
 
There's no set-up screen on the D200, baud rate and parity are set on the rear switches.

To go online, use CMD-Online. The rear DB-15 is wired conventionally. You'll need to tie the modem control lines together - DTR to (DSR, CD and CTS) and use pin 7 for GND, and 2 & 3 for TX and RX. Standard RS-232 connections, but modem signals have to be satisfied.

You should be able to talk to it from a PC.
 
D200 reference manual & schematics

D200 reference manual & schematics

Contact me if you need schematics or reference manual for the D200:

ka1axy73-at-hotmail-dot-com

Peter
 
Dg terminal

Dg terminal

Hi All;
For Schematics and Info .. Look up Bruce Ray of WildHare Computers fame .. He is the main Source for Data General Stuff... He is not at home right now , But he will be back after the middle of the Month , if you don't hear from Him... :) :)
THANK YOU Marty
 
You must log in or register to reply here.
Back
Top