Smart Home Meets Dumb Terminal

Most smart home products are designed to be controlled from a mobile device, which makes sense since that’s what the average consumer spends most of their day poking around on these days. But you aren’t the average consumer, are you? If you’re looking for a somewhat more tactile experience, then why not put your smart home dashboard on a vintage serial terminal as [Daniel Karpantschof] did?

So how do you get the latest and greatest in home automation talking to a serial terminal built before the Internet as we know it? With Python, of course. [Daniel] has some code running on a Linux server that’s actually taking to his various smart home gadgets, which then spits out a simple ASCII user interface that his circa 1976 ADM-3A terminal can handle; complete with a floor plan view of the house that shows the temperature in different rooms.

Naturally, that’s only half the battle. You still need to get that interface onto the terminal. For that, [Daniel] is using the “Simulant Retro WiFi Modem” that we’ve covered in the past. An ESP8266 connects to the network and shuffles data over to the target device over serial. It’s all transparent to the terminal itself, so this project could be reproduced with whatever vintage machine holds a special place in your heart.

20 thoughts on “Smart Home Meets Dumb Terminal

  1. Oh, if I had a Lear Siegler I would have to be in there, swapping out the character gen ROM for a code page 850 one, so I could draw boxes on the screen that joined up. I note one thing I have never noticed about the font – the one I used to use was upper case only – but the lower case letters are shifted up in the character box. I guess that is because there are only 7 rows of pixels for a character.

    Of course Code Page 850 would only work if the display memory were 8 bit, and I can’t even be sure that it wasn’t just 7 bits.

    Love the project, btw. I have an old G3 iMac running an extremely old version of YellowDog Linux in the loft, which acts as a serial terminal I can plug into switches in the small (4U) rack. It has that same endearing quality of design. It’s just 20 years old, not 40.

    1. Having found up the service manual … they place 6, 7, 12, or 14 RAMs to produce a 6- or 7- bit wide character specifier for the character generator ROMs.

      The other problem is that the chargen always adds padding around the 5×7 pixel bitmaps in the ROMs; it’d be easy to add a wider ROM and connect two extra pins to the output stage shift register, but I didn’t trivially see how it generated the vertical padding.

      1. Following up on this: it looks like the top and bottom rows of each 9-scanline-tall character (i.e. scanlines 0 and 8) are always drawn from the same data. Box-drawing characters will be tricky.

    2. I think I have a way to make you jealous. Imagine having one with an rg-512 board for pixel perfect drawing based on the tektronix vector storage terminal commands. I may modify the scripts here to do that, it’ll look a lot cleaner

  2. I recognized the curve of that ADM-3A screen before I read that far. I found a similar model (ADM-5? I can’t remember) ~20 years ago that was non-functional but I was at least able to confirm it had raster before storing it away until I had enough skill and tools (and free time) to fix it properly. It wasn’t easy since the black level is so black; I think I glitched it just enough to show a character or two. Maybe its UART was bad, I dunno. It’s time to look for it now.

    Lear Siegler just had such an awesome ’70s futuristic design asthetic.

  3. I used to keep.a Mac Classic around in case I needed a terminal, but after getting a couple of Mac laptops, decided those were a better choice. But really, I never needed a terminal.

  4. Reminds me of two others. Ciarcia’s Circuit Cellar class homebrew home automation of the late 70s tended to look like this. Secondly mid 80s to mid 90s, actual highish end, commercial building management systems looked mostly the same, but they got a splash of color and were often touch screen or light pen operated. The late 90s kinda went “ditto but with mono LCD”

  5. “why not put your smart home dashboard on a vintage serial terminal”

    Because it wastes a lot power just to get a certain aesthetic? Seriously, CRTs devour electricity.

    1. Mono are only about a 3rd that of color. In fact 12-14″ ones probably compare well with a “Thrift store cheapy” i.e. older. 14-15″ LCD flat panel.

      1. My vintage terminal draws 150W in contrast to a modern 24 core server drawing 140W for example. Regarding colour versus mono, I believe you’re confusing LCD and phosphorous technologies?

        1. That’s probaldy 200 TTL chips sucking a lot of that I guess, which I did forget about in the context of using old terminals. But mono CRT uses maybe a 12kV HV coil vs color with 20-30kV then you’ve got 3x the beams, which all have to be more powerful because half is wasted bouncing off the dot mask vs lighting phosphor. Then you’ve got twice the circuitry for the color decoding, then 3 times the drivers. I have a feeling also that they used more efficient phosphors for monos, rather than requiring specific colors though so less electrons required per lumen of glow.

          anyhoo, real figures for example, 14″ LCD TV from approx 2007 probably a fluorescent or gas discharge backlight, 60W on back, RCA late 70s 12″ B/W CRT TV, 25W on back, Goldstar late 80s 14″ CRT TV/Monitor Colour 85W on back, NEC Accusync mid noughties 16″ Colour LCD 46W.. More modern LCD/LED probably come in around 20W on a small one, but the problem is we keep buying bigger, so ppl getting 17, 19, 21″ at same wattage every 5 years or so. Technically the older accusync is less efficient at 46W 16″ but if you gonna replace with a 27″ ultrawide, you’re not gonna see much difference on the electric bill. Then ecologically you start about 1000 kilowatt hours in the hole from embedded energy of manufacture, which takes 10 years to work off if you use it 2 hours a day.

          So yes, while you might want to pause before running something with a lot of TLL in sucking sig fractions of a watt per chip 24/7, don’t let some eco-troll with a greenwash brush guilt you into NOT using available mono TV or monitor for a arduino basic computer or CP/M on a chip system on the grounds of CRTs being thirsty, because they are likely less thirsty than many of the cheap used LCD monitors if you go VGA bit bang instead of TVout, but even should you have the cash for the most modern you’ve got to use it a heck of a lot for years until the invested energy is paid back in efficiency.

    2. Right, so making something that faithfully spits out ‘hello world’ is ok, as it uses less electricity? If one is to begin assessing what is and what is not a waste of resources, the entire build stuff community is all but lost, which is heading that way anyway, but I digress. Seriously, take a look at the archives. Let me ask, where does the waste of resource begin?

  6. This is exactly my plan for my commodore PET. I love how Fallout this kind of setup feels – especially because my house is from the 50s. For those worried about power usage, it won’t be running unless I’m interacting with it. Going to put the program directly in rom for instant boot.

    Plus running an old crt 24/7 is not a great idea… They have a limited life.

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