Ask Hackaday: Did Video Games Influence Your Career?

Apex Minecraft hosting recently held a scholarship competition. The person who sent in the best essay would win a $2,000 scholarship.  The winning essay starts, “Five years ago, at age 13, I built an entire computer from scratch. Assembled from basic components: wires, torches, repeaters, pistons, and blocks, it was capable of rendering images to a display, multiplying and dividing numbers, and even calculating square roots.” I  had to read it twice before it clicked that he was talking about a computer built entirely in a fictional universe.

It’s no wonder that he’s now a freshman at college, pursuing a degree in computer engineering. After reading this, I started to reminisce. The first computer I ever had access to was my mother’s laptop. It had an install of QBASIC on it, and I remember using it to make a few text based games. Later on when we got our first family computer I remember spending hours getting no better at video game programming using QBASIC.

It went on and on. I remember doing AI for video games in DarkBasic. I remember doing physics and collisions. Eventually I found my way to html, then php, to make websites about games (which are too terrible to share with you). So when the time came to program robots I was absolutely fearless. It just seemed like such a natural extension of what I already knew that it never occurred to me to be thankful for the time I spent trying to make my own simple little games until much later.

In the end I am still occasionally making little forays into game programming when I want to learn a new language or get back up to speed. It never occurred to me that perhaps this was just the way I’ve always learned a language.

Later on in the winner’s essay he goes on to describe his minecraft community. They taught new players. They taught themselves. They hung out and became friends. The writer gained a sense of self as a user of computers, a teacher of skills, a good member of a community, and a solver of problems. Unlike some of his classmates he won’t go to college and have to learn if he’s good enough. He’ll already know. All it took was a silly block based game.

Did any of you have seemingly frivolous endeavors show up as a foundation for your life and learning far into the future? Tell in the comments below how this ended up shaping your career.

Ask Hackaday: How Do You Convert Negative Voltages to Positive?

I have a good background working with high voltage, which for me means over 10,000 volts, but I have many gaps when it comes to the lower voltage realm in which RC control boards and H-bridges live. When working on my first real robot, a BB-8 droid, I stumbled when designing a board to convert varying polarities from an RC receiver board into positive voltages only for an Arduino.

Today’s question is, how do you convert a negative voltage into a positive one?

In the end I came up with something that works, but I’m sure there’s a more elegant solution, and perhaps an obvious one to those more skilled in this low voltage realm. What follows is my journey to come up with this board. What I have works, but it still nibbles at my brain and I’d love to see the Hackaday community’s skill and experience applied to this simple yet perplexing design challenge.

The Problem

RC toy truck and circuit with no common
RC toy truck and circuit with no common

I have an RC receiver that I’ve taken from a toy truck. When it was in the truck, it controlled two DC motors: one for driving backwards and forwards, and the other for steering left and right. That means the motors are told to rotate either clockwise or counterclockwise as needed. To make a DC motor rotate in one direction you connect the two wires one way, and to make it rotate in the other direction you reverse the two wires, or you reverse the polarity. None of the output wires are common inside the RC receiver, something I discovered the hard way as you’ll see below.

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Ask Hackaday: DIY Handwriting Recognition

Computer handwriting recognition is very cool by itself, and it’s something that we’d like to incorporate into a project. So we went digging for hacker solutions, and along the way came up with an interesting bit of history and some great algorithms. We feel like we’ve got a good start on that front, but we’re stuck on the hardware tablet sensor itself. So in this Ask Hackaday, we’re going to make the case for why you could be using a tablet-like device for capturing user input or doing handwriting recognition, and then we’re going to ask if you know of any good DIY tablet designs to make it work.

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Ask Hackaday: How Do You Make A Hotplate?

Greetings fellow nerds. The Internet’s favorite artificial baritone chemist has a problem. His hotplates burn up too fast. He needs your help to fix this problem.

[NurdRage] is famous around these parts for his very in-depth explorations of chemistry including the best ways to etch a PCB, building a thermometer probe with no instructions, and chemical synthesis that shouldn’t be performed by anyone without years of experience in a lab. Over the past few years, he’s had a problem: hotplates suck. The heating element is usually poorly constructed, and right now he has two broken hotplates on his bench. These things aren’t cheap, either: a bare-bones hotplate with a magnetic stirrer runs about $600.

Now, [NurdRage] is asking for help. He’s contacted a few manufacturers in China to get a hundred or so of these hotplate heating elements made. Right now, the cost for a mica and metal foil hotplate is about $30 / piece, with a minimum order quantity of 100. That’s $3,000 that could be better spent on something a bit more interesting than a heating element, and this is where you come in: how do you build the heating element for a hotplate, and do it cheaply?

If you buy a hotplate from the usual lab equipment supplier, you’ll get a few pieces of mica and a thin trace of metal foil. Eventually, the metal foil will oxidize, and the entire hotplate will stop working. Repairs can be done with copper tape, but by the time that repair is needed, the heating element is already on its way out.

The requirements for this heating element include a maximum temperature of around 350 ºC. That’s a fair bit hotter than any PCB-based heat bed from a 3D printer gets, so consider that line of reasoning a dead end. This temperature is also above what most resins, thermoplastics, and composites can handle, which is why these hotplates use mica as an insulator.

Right now, [NurdRage] will probably end up spending $3,000 for a group buy of these heating elements. That’s really not that bad – for the price of five hotplates, he’ll have enough heating elements to last through the rest of his YouTube career. There must be a better way, though, so if you have an idea of how to make a high-temperature heating element the DIY way, leave a note in the comments.

Ask Hackaday: Help Me Choose A ‘Scope

If there is one instrument that makes an electronic engineer’s bench, it is the oscilloscope. The ability to track voltages in the time domain and measure their period and amplitude is one akin to a light in the darkness, it turns a mere tinkerer with circuits into one in command of them. Straightforward add-on circuits can transform a basic oscilloscope into a curve tracer, frequency response display, and much more, and modern oscilloscopes offer a dizzying array of useful measurement features unimaginable to engineers only a few years ago. And I need your help to pick a new one.

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Ask Hackaday: Are Gaming PCs Hard to Build?

No. No they’re not. But let’s talk about it anyway.

The endless trenches of digital worlds are filled with hardcore gamers from all walks of life. They can be found exploring post-apocalyptic Boston in Fallout 4, and commanding Sgt. Recker through a war-torn landscape in Battlefield 4 for hours on end. Their portal into these vast digital worlds come via some sort of computer system.

What type of computer system used is a point of contention between many gamers, and is typically divided between console versus PC. I will not dare to drag you into the captious arguments between the two, but instead we will focus on something that has something in common with our world — how does a previously non-technical console enthusiast cross over and build a gaming PC?

Many hackers have built computers from scratch and [Adam Fabio] just covered a bunch of custom laptop builds this morning. People with such skills can easily build a high-end gaming PC. But what about people without such skills? Can a console gamer with no technical background build a high-end PC gaming system?

Inspiration for this article came after reading something [Emanuel Maiberg] published over the summer on Motherboard. Why someone writing for a publication called Motherboard would have trouble building a gaming rig is beyond me. Certainly I think his starting assumptions are questionable. He asserts that you need an unreasonable amount of time and money to attempt one of these projects. But gaming rigs can be purchased fully-assembled — those that build them are doing it out of passion.

The question is this:  How far should engineers go to make a technical product easier to use for a non-technical person?  If I order an engine for a hot rod, it can be assumed that I know to hook up the gas line without specifically being told to do so. After all, a person who’s going to put an engine in a hot rod probably knows a thing or two about engines.

I think that building a desktop PC has never been easier. We’ve now had 30 years of evolution to help weed out the “slow learners” when it comes to manufacturers. The Internet is a lot easier to use for answers than it used to be, and we have faster means of connecting with communities of experts than ever before.

That said, the neighborhood computer store is beginning to go the way of the dodo. There is an entire generation of “mobile-first” users who will give you a blank stare if you start talking about “desktop computing”. And familiarity with the fact that computer customization is even possible is beginning to fade; if all you’ve ever used are tablets and smartphones “upgrade” and “customization” are software terms, not hardware possibilities.

So we turn it over to you. Are gaming PCs hard to build? Have engineering practices and design choices made it easier than it used to be to get into it? What do you think is happening with the average skill level for working with computers now compared to when you had to open the case to add a modem to your machine? Let us know what you think in the comments below.

Ask Hackaday: Calling All 68k Experts

This is a tale of old CPUs, intensive SMD rework, and things that should work but don’t.

Released in 1994, Apple’s Powerbook 500 series of laptop computers were the top of the line. They had built-in Ethernet, a trackpad instead of a trackball, stereo sound, and a full-size keyboard. This was one of the first laptops that looked like a modern laptop.

The CPU inside these laptops — save for the high-end Japan-only Powerbook 550c — was the 68LC040. The ‘LC‘ designation inside the part name says this CPU doesn’t have a floating point unit. A few months ago, [quarterturn] was looking for a project and decided replacing the CPU would be a valuable learning experience. He pulled the CPU card from the laptop, got out some ChipQuick, and reworked a 180-pin QFP package. This did not go well. The replacement CPU was sourced from China, and even though the number lasered onto the new CPU read 68040 and not 68LC040, this laptop was still without a floating point unit. Still, it’s an impressive display of rework ability, and generated a factlet for the marginalia of the history of consumer electronics.

Faced with a laptop that was effectively unchanged after an immense amount of very, very fine soldering, [quarterturn] had two choices. He could put the Powerbook back in the parts bin, or he could source a 68040 CPU with an FPU. He chose the latter. The new chip is a Freescale MC68040FE33A. Assured by an NXP support rep this CPU did in fact have a floating point unit, [quarterturn] checked the Mac’s System Information. No FPU was listed. He installed NetBSD. There was no FPU installed. This is weird, shouldn’t happen, and now [quarterturn] is at the limits of knowledge concerning the Powerbook 500 architecture. Thus, Ask Hackaday: why doesn’t this FPU work?

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