Author: Al Williams

4351 Articles

Inside The Atari 2600

January 15, 2023 by 17 Comments

The Atari 2600 was an extremely popular yet very simple game console back in the 1970s. They sold, apparently, over 30 million of them, and, of course, these things broke. We’d get calls from friends and — remember, back then normal people weren’t computer savvy — nine times out of ten, we’d ask them to swap the controllers to show them it was a bad controller, and problem solved. But if you did have to open one up, it was surprising how little there was inside, as [Steve] notes in his recent teardown.

The bulk of the circuit board was switches, the power supply, and a TV modulator if you remember those. The circuit board was a tiny thing with a shrunk-down 6502, a 6532 RIOT chip, and a custom chip called a TIA. If you are familiar with those chips, you might wonder if the TIA had any memory in it. It didn’t. Nearly all the ROM and RAM for the game lived in the cartridge itself. Sure, the RIOT has 128 bytes of memory, but that’s not much.

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Microsoft Returns To The Altair

January 15, 2023 by 25 Comments

The Altair 8800 arguably launched Microsoft. Now [Dave Glover] from Microsoft offers an emulated and potentially cloud-based Altair emulation with CP/M and Microsoft Basic. You can see a video of the project below. One thing that makes it a bit odd compared to other Altair clones we’ve seen is that the emulator runs in a Docker environment and is fully cloud-enabled. You can interact with it via a PCB front panel, or a terminal running in a web browser.

The core emulator is MIT-licensed and seems like it would run nearly everywhere. We were a little surprised there wasn’t an instance in the Azure cloud that you could spin up to test drive. Surely a few hundred Altairs running at once wouldn’t even make a dent in a modern CPU.

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Conductive Ink Based On A Simple Idea

January 14, 2023 by 15 Comments

There’s an old series of jokes that starts with: “How do you put an elephant in a refrigerator?” The answer is to open the door, put the elephant inside, and close the door. Most people don’t get that because it is too simple, and simple is the approach Georgia Tech researchers have taken when faced with the problem of using a particular conductive plastic. PEDOT, the plastic in question, is a good conductor, but it is hard to work with. You can add materials to make it easier to work with, but that screws up the conductivity. Their answer is much like the refrigerator joke: add material to PEDOT, paint or print it where you want, and then remove the extra material. Simple.

The polymer needs side chains to be soluble. This allows you to mix an ink or paint made of the material, but the waxy side chains interfere with the material’s conductivity. However, after application, it is possible to break off the side chains and flush them out with a common solvent. The process is simple, and leaves a flexible conductive material that’s stable.

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Lunar Rover Is No Toy

January 11, 2023 by 21 Comments

When you think of Tomy — more properly, Takara Tomy — you think of toys and models from Japan. After all, they have made models and toys as iconic as Transformers, Thomas, Jenga, Boggle, and Furby. They also made figures associated with Thunderbirds and Tron, two favorites in our circles. However, their recent design for SORA-Q is no toy. It is a tiny lunar rover designed at the request of JAXA, the Japanese space agency. The New Yorker recently posted about how this little rover came about.

The SORA-Q looks a bit like a modern Star Wars drone or — if it could fly — a training drone from some of the older movies. The rover caught a lift from a SpaceX Falcon 9 towards the moon with the Hakuto-R M1 lander. Another SORA-Q is scheduled to touch down later this year.

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NASA Help Wanted: Telescope Optional

January 11, 2023 by 31 Comments

If you’ve ever wanted to work for NASA, here’s your chance. Well, don’t expect a paycheck or any benefits, but the Agency is looking for volunteers to help process the huge amount of exoplanet data with their Exoplanet Watch program. If you have a telescope, you can even contribute data to the project. But if your telescope is in the back closet, you can process data they’ve collected over the years.

You might think the only way to contribute with a telescope is to have a mini-observatory in your backyard, but that’s not the case. According to NASA, even a six-inch telescope can detect hundreds of exoplanet transits using their software. You might not get paid, but the program’s policy requires that the first paper to use work done by program volunteers will receive co-author credit on the paper. Not too shabby!

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Dead Washer Lives Again With ATTiny

January 11, 2023 by 59 Comments

We aren’t saying that appliances are a scam, but we have noticed that when your appliances fail, there’s a good chance it will be some part you can no longer get from the appliance maker. Or in some cases, it’s a garden-variety part that should cost $2, but has been marked up to $40. When [Balakrishnan] had a failure of the timer control board for a Whirlpool washing machine, it was time to reverse engineer the board and replace it with a small microcontroller.

Of course, this kind of hack is one of those that won’t help you unless you need exactly that timer board. However, the process is generally applicable. Luckily, the motherboard chip was documented and the timer control board used a simple ATmega88, so it was easy to see that the devices were communicating via I2C.

Reading the I2C  bus is easy with a logic analyzer, and this revealed the faulty device’s I2C address. The board that failed was only for display, so a simple program that does nothing other than accept I2C data put the washer in working order. Once it was working with an Arduino, an ATTiny45 did the work with a lot less space and cost.

If you don’t want to reverse engineer the washing machine, you could just replace all the controls. That even works if the old washer wasn’t electronic to start.

Variable Width 3D Printing The Hard Way

January 11, 2023 by 22 Comments

The problem: you want to produce varying line thicknesses when 3D printing. The solution, if you are the Liqtra company, appears to be to put seven print heads together and enable one for thin lines, all of them for thick lines, and something in between for everything else. The technical details are scant, but from the video below and some pictures, you can get a general idea.

There are some obvious benefits and drawbacks. You’d expect that for the right kind of part, this would be fast since you are essentially laying down seven tracks at once. The downside is your track width varies in pretty course steps, assuming you have to use the maximum width of each nozzle to prevent gaps. New slicing software is a must, too.

The demos and pictures show multiple filament colors because it photographs well, but you’d assume in practice that you would use seven spools of the same material. The good thing is that you could print with a single nozzle where that’s important. We assume all the nozzles are the same size, and that will control the practical layer height, but that’s a small price to pay.

The company claims a much faster print, but as we mentioned, this will depend on the specific printed part. They also claim inter-layer strength increases as well, although we found that surprising. This is probably overkill for home users, but we imagine this would be an interesting technology for people trying to run production quantities through a printer.

We don’t remember seeing this approach with a homebrew printer, although having multiple extruders into one or multiple nozzles isn’t unusual anymore. It seems like you could experiment with this kind of technology pretty readily. Of course, there’s more than one way to speed up production.

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