What’s your favorite color? Don’t tell us, Tweet it to [Sebastian’s] favorite color Twitter display and you’ll be contributing to the artwork hanging on his wall.
This answers a very important question, what do you do with your projects after they’re completed? For us the best part is the planning and building. Once it’s done the thrill is pretty much gone for us. We haven’t even switched on our Ping Pong clock in over a year. But [Sebastian] recently dusted his 10×10 LED matrix for this project.
Tweets are parsed by a Python project he wrote to try out the Twitter API. It looks for a set list of colors . He asserts that people aren’t that creative when you solicit their favorite color but to prove him wrong we’re going to say our favorite is Amaranth. After it finds the color it pushes it to the next pixel in the spiraling pattern shown above. But wait, there’s more! To give the pixels a but if extra meaning he uses the total length of the tweet to set intensity.
[Aaron] just finished building an online 595 shift register simulator. These inexpensive chips let you extend the number of devices that can be controlled by a single microcontroller. You see them in quite a few LED multiplexing projects, included the Ping Pong Clock that we recently built. But they can be a bit tricky to fully grasp if you’re not familiar with the hardware.
This simulator gives you a point-and-click interface for the five possible control lines on a 595 shift register. There are three pins that must be manipulated to use the device; the serial in, clock, and latch pins. The other two are for clearing the register, and enabling output and can be considered optional. You can choose to control these with a microcontroller in your own projects for more flexibility, but often they are tied to either VCC or GND (depending on the chip) when these features are unnecessary. Give this simulator a try and then take what you learned over to a solderless breadboard and see if you can write some firmware to produce the same results. If you’re still having trouble you can take a look at this 595 tutorial for further information.
[Xander Naumenko] has created something truly impressive — a working RISC-V CPU completely contained in a Terraria world. And then for added fun, he wrote the game of pong, playable in real time, from within the game of Terraria. It’s all based on the in-game wiring system, combined with a bit of a hack that uses the faulty lamp mechanic to create a very odd AND gate. In Terraria, the existing logic gates have timing issues that make them a no-go for complicated projects like this one. The faulty lamp is intended to do randomized outputs, by stacking multiple inputs to get a weighted output when a clock signal is applied. The hack is to simply give this device a single input, turning it into a clocked IF gate. Two of them together in series makes a clocked AND gate, and two in parallel make a clocked OR gate.
Why would [Xander] embark on this legendary endeavor? Apparently after over eight thousand hours clocked in game, one gets a bored of killing slimes and building NPC houses. And playing with the game’s wiring system turned on a metaphorical lightbulb, that the system could be used to build interesting systems. A prototype CPU, with a completely custom instruction set came next, and was powerful enough to compute Fibonacci. But that obviously wasn’t enough. Come back after the break for the rest of the story and the impressive video demonstration.
This week, Editor-in-Chief Elliot Williams and Assignments Editor Kristina Panos delighted in the aural qualities of Kristina’s brand new, real (read: XLR) microphone before embarking on creating a podcast highlighting the best of the previous week’s hacks.
This week in the news, NASA returned to the Moon with Artemis I, and this time, there are CubeSats involved. After that, it’s on to the What’s That Sound results show, marred by Kristina’s cheating scandal (listening ahead of time) and Elliot’s reading the filename aloud before we started recording. Finally, we move on to the hacks — they start with a trip to the 90s both sonically and visually, and end with a really nice alarm clock that’s decidedly 70s, and definitely Hackaday.
Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
[Joe Wingbermuehle] has an interest in computers-of-old, and some past experience of building computers on perfboard from discrete transistors, so this next project, Q2, is a complete implementation of a PDP8-like microcomputer on a single PCB. Like the DEC PDP-8, this is a 12-bit machine, but instead of the diode-transistor logic of the DEC, the substantially smaller Q2 uses a simple NMOS approach. Also, the DEC has core memory, but the Q2 resorts to a pair of SRAM ICs, simply because who wants to make repetitive memory structures with discrete 2N7002 transistors anyway?
SMT components for easy machine placement
Like the PDP-8, this machine uses a bit-serial ALU, which allows the circuit to be much smaller than the more usual ALU structure, at the expense of needing a clock cycle per bit per operation, i.e. a single ALU operation will take 12 clock cycles. For this machine, the instruction cycle time is either 8 or 32 clocks anyway, and at a maximum speed of 80 kHz it’s not exactly fast (and significantly slower than a PDP-8) but it is very small. Small, and perfectly formed.
The machine is constructed from 1094 transistors, with logic in an NMOS configuration, using 10 K pullup resistors. This is not a fast way to build a circuit, but it is very compact. By looking at the logic fanout, [Joe] spotted areas with large fanouts, and reduced the pull-up resistors from 10 K to 1 K. This was done in order to keep the propagation delay within bounds for the cycle time without excessive power usage. Supply current was kept to below 500 mA, allowing the board to be powered from a USB connector. Smart!
Memory is courtesy of two battery-backed 6264 SRAMs, with the four 12-bit general purpose registers built from discrete transistors. An LCD screen on board is a nice touch, augmenting the ‘front panel’ switches used for program entry and user input. A 40-pin header was added, for programming via a Raspberry Pi in case the front panel programming switches are proving a bit tedious and error prone.
Discrete transistor D-type flip flop with indicator. Latest circuit switched to 2N7002 NMOS.
In terms of the project write-up, there is plenty to see, with a Verilog model available, a custom programming language [Joe] calls Q2L, complete with a compiler and assembler (written in Rust!) even an online Q2 simulator! Lots of cool demos, like snake. Game of Life and even Pong, add some really lovely touches. Great stuff!
Join Hackaday Editor-in-Chief Elliot Williams and Managing Editor Tom Nardi as they ring in the New Year with the first podcast episode of 2022. We get the bad news out early for those still thumbing away at their Blackberries, then pivot into some of the highlights from over the holidays such as the release of NODE’s The Pinouts Book and the discovery of a few expectation-defying OpenSCAD libraries. We’ll look at modifying a water cooler with Ghidra, and the incredible technology that let’s historians uncover the hidden history of paintings. Oh, and we’ll also talk about all the best and most important stories of the last 12 months. There’s a lot of ground to cover, so get comfortable.
Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
Many an automotive enthusiast finds themselves at a track day eventually. Typically, this involves competing against the clock to better one’s laptimes in short sessions throughout the day. Such events are fun, but it often creates a perishing thirst for a greater level of competition.
Regularity and endurance events are often the next step up for a lot of people. These events involve long runs at race pace that stress a car to (or beyond!) the breaking point. Careful preparation is required if one is to see out the race to the chequered flag. Let’s break down what you’ll need to consider.
