VT100 Oscilloscope

February 26, 2010 6:42 AM

Use the Internets the way God intended, on a VT100 oscilloscope.
posted by pashdown (13 comments total)

A great thing about the Terminalscope is its simplicity.

There are a lot of words you could use to describe this project, but "simplicity" would be fairly far down on the list.
posted by Horace Rumpole at 6:55 AM on February 26, 2010 [3 favorites]

That is one of the most beautifully useless things ever. I love it.
posted by ardgedee at 7:00 AM on February 26, 2010 [1 favorite]

It's a serial link, a D/A converter and a few bits and bobs to make the beam scan up/down and left right across the screen. As display technology goes it is pretty simple.
posted by vbfg at 7:05 AM on February 26, 2010

Back in the 80s I had a circuit that could play Pong on an oscilloscope. As vbfg says, displaying raster-scan video on a scope is fairly simple.
posted by rocket88 at 7:19 AM on February 26, 2010

Well, dunno about clever. It is a video card, with serial bus. The difference from a 'regular' video card that you can now run your raster at whatever rate you want to, not being constrained by someone else's concept of sync, etc. Typically this kind of set-up flickers like crazy (most of us older hacker types have done some kind of computer output to scope deal, I think, just usually not with a rasterizer) due to the poor speed and the persistence profile of the phosphors in a scope. Of course, some scopes have more persistence then others, and if your chips are running a good speed (and your scope is even remotely modern), you can get the refresh rates up to acceptable.

Aesthetically and conceptually it is a lovely idea.
posted by Bovine Love at 7:22 AM on February 26, 2010

Mmmmmmm... green on black. = )
posted by PROD_TPSL at 8:34 AM on February 26, 2010

I can get behind almost anything that includes a breadboard and the internet console in the same project. Thanks for this.
posted by drowsy at 8:48 AM on February 26, 2010

I thought this was going to be an oscilloscope in a VT100 terminal. I'm not nearly so impressed that it is the reverse.
posted by chairface at 9:12 AM on February 26, 2010 [4 favorites]

Ha, yes, I also wondered from the title if it would be an ASCII-art oscilloscope, which would be even more supremely useless than this. I might have to build one.
posted by hattifattener at 9:41 AM on February 26, 2010

But will it run MaME?
posted by wcfields at 9:47 AM on February 26, 2010

I approve.
posted by jscott at 2:14 PM on February 26, 2010

Oh man, I haven't seen anything like this since the early microcomputer homebrew days, when we all lusted for those newfangled (and expensive) CRT terminals, and pored over cryptic design books like Don Lancaster's "TV Typewriter Cookbook."
posted by charlie don't surf at 4:18 PM on February 26, 2010

Rather than draw each character with individual strokes, op-amps are used to generate a raster scan across the screen (like a TV) and the Z axis (beam intensity) is modulated directly by the microcontroller.

WOW. That is some serious microcontroller programmin' there. I'm humbled.
posted by DecemberBoy at 5:53 PM on February 26, 2010