A Web-Based Graphics Editor For Tiny Screens

These days, adding a little LCD or OLED to your project is so cheap and easy that you can do it on a whim. Even if your original idea didn’t call for a display, if you’ve got I2C and a couple bucks burning a hole in your pocket, why not add one? Surely you’ll figure out what to show on it as the project develops.

But that’s where it can get a little tricky — in terms of hardware, adding a screen just takes running a few extra wires, but the software side is another story. Not only do you have to contend with the different display libraries, but just creating the image assets to display on the screen can be a hassle if it’s not something you do regularly. Enter Lopaka, a graphics and user interface editor for electronic projects created by [Mikhail Ilin].

More after the break…

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Multitasker Or Many Monotaskers?

In Al Williams’s marvelous rant he points out a number of the problems with speaking to computers. Obvious problems with voice control include things like multiple people talking over each other, discerning commands from background conversations, and so on. Somehow, unlike on the bridge in Star Trek, where the computer seems to understand everyone just fine, Al sometimes can’t even get the darn thing to play his going-to-sleep playlist, which should be well within the device’s capabilities.

In the comments, [rclark] suggests making a single button that plays his playlist, no voice interaction required, and we have to admit that it’s a great solution to this one particular problem. Heck, the “bedtime button” would make fun project in and of itself, and it’s such a limited scope that it could probably only be an weekend’s work for anyone who has touched the internals of their home automation system, like Al certainly has. We love the simplicity of the idea.

But it ignores the biggest potential benefit of a voice control system: that it’s a one-size-fits-all solution for everything. Imagine how many other use cases Al would need to make a single button device for, and how many coin cell batteries he’d be signing himself up to change out over the course of the year. The trade-off is that the general purpose solution tends not to be as robust as a single-tasker like the button, but also that it can potentially simplify the overall system.

I suffer this in my own home. It’s much more a loosely-coupled web of individual hacks than an overall system, and that has pros and cons. Each individual part is easier to maintain and hack on, but the overall system is less coordinated than it could be. If we change the WiFi password on the home automation router, for instance, I’m going to have to individually log into about eight ESP8266s and change their credentials. Yuck!

It’s probably a matter of preference, but I’ll still take the loose, MQTT-based system that I’ve got now over an all-in-one. Like [rclark], I value individual device simplicity and reliability above the overall system’s simplicity, but because our stereo isn’t even hooked up to the network, I can’t play myself to sleep like Al can. Or at least like he can when the voice recognition is working.

The Perfect Pi Pico Portable Computer

[Abe] wanted the perfect portable computer. He has a DevTerm, but it didn’t quite fit his needs. This is Hackaday after all, so he loaded up his favorite CAD software and started designing. The obvious choice here would be a Raspberry Pi. But [Abe] didn’t want to drop in a Linux computer — he was going for something a bit smaller.

An RP2040 Pico would be a perfect fit. Driving a display with the Pico can be eat a lot of resources though. The solution was a PicoVision from Pimoroni. PicoVision uses two RP2040 chips. One drives an HDMI port, while the other is free to run application software. This meant a standard HDMI screen could be used.

The keyboard was a bit harder. After a lot of searching, [Abe] found an IR remote designed for smart TVs. The QWERTY keyboard was the perfect size but didn’t have an interface he could use. He fixed that with an adapter PCB including an I2C GPIO expander chip. A bit of I2C driver software later, and he had a working input keyboard.

Hardware doesn’t do anything without software though. The software running on the handheld is called Slime OS, and the source is available at [Abe’s] GitHub. It’s a launcher, with support for applications written in python. [Abe] has a few basic demos working, but he’s looking for help to get more features up and running.

Although it wasn’t quite what [Abe] was after, our own [Donald Papp] came away fairly impressed when he gave the DevTerm a test drive back in 2022. Something to consider if you’re looking for a Linux handheld and not quite ready to build one yourself.

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Tricked Out Miter Fence Has All The Features

“World’s best” is a mighty ambitious claim, regardless of what you’ve built. But from the look of [Marius Hornberger]’s tricked-out miter fence, it seems like a pretty reasonable claim.

For those who have experienced the torture of using the standard miter fence that comes with machine tools like a table saw, band saw, or belt sander, any change is likely to make a big difference in accuracy. Miter fences are intended to position a workpiece at a precise angle relative to the plane of the cutting tool, with particular attention paid to the 90° and 45° settings, which are critical to creating square and true joints.

[Marius] started his build with a runner for the T-slot in his machine tools, slightly undersized for the width of the slot but with adjustment screws that expand plastic washers to take up the slack. An aluminum plate equipped with a 3D printed sector gear is attached to the runner, and a large knob with a small pinion mates to it. The knob has 120 precisely positioned slots in its underside, which thanks to a spring-loaded detent provide positive stops every 0.5°. A vernier scale also allows fine adjustment between positive stops, giving a final resolution of 0.1°.

Aside from the deliciously clicky goodness of the angle adjustment, [Marius] included a lot of thoughtful touches. We particularly like the cam-action lock for the angle setting, which prevents knocking your fine angle adjustment out of whack. We’re also intrigued by the slide lock, which firmly grips the T-slot and keeps the fence fixed in one place on the machine. As for the accuracy of the tool, guest meteorologist and machining stalwart [Stefan Gotteswinter] gave it a thumbs-up.

[Marius] is a veteran tool tweaker, and we’ve featured some of his projects before. We bet this fence will see some use on his much-modified drill press, and many of the parts for this build were made on his homemade CNC router.

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