The humble business card is usually a small slip of cardboard with some basic contact details on it — but as hackers know, it can be so much more. [Marian] has provided us a great example in the form of his own digital business card, which doubles as a handheld game!
Wanting to make his business card more interesting for better engagement, [Marian] was inspired by the Arduboy to give it some interactivity. He chose the STM32G030F6 microcontroller as a cheap and reliable option to run his business card. He then created a 10×9 LED matrix display using Charlieplexing to minimize the amount of I/O pins required. For controls, he went with the usual directional cross plus two action buttons. He implemented a variety of games on the card—including a Flappy Bird clone and a game similar to the classic Simon toy.
It was probably a reasonable assumption that the “Tiny” in our recently concluded Tiny Games Contest mostly referred to the physical footprint of the game. And indeed, that’s the way most of the entries broke, which resulted in some pretty amazing efforts. [Anders Nielsen], however, took the challenge another way and managed to stuff a seagull-centric side-scroller into just 500 bytes of code.
That’s not to say that the size of [Anders]’s game is physically huge either. Flappy Larus, as he calls his game, runs on his popular 65uino platform, a 6502 microcontroller in the familiar Arduino Uno form factor. So it’s pretty small to begin with, and doesn’t even need any additional components other than the tiny OLED screen which has become more or less standard for the 65uino at this point. The only real add-on is a piezo speaker module, which when hooked up to the I2C data line happens to make reasonable approximations of a squawking seagull, all without adding a single byte of code. Check out a little game play in the video below.
Should you happen to have an HP7440A or similar plotter hanging around, you could have a quick game of Flappy Bird — or Plotty Bird as [WesleyAC] calls it. Just be sure you have some blank paper. The whole thing fits in about 200 lines of Rust code and — according to the author — gets to about 20 frames per second.
Watching the thing go, it appears that it draws a random set of pipes and then traces your flight path on the same page in real time.
We often think that less is more, but what can you do with a device that has only a single button? [Danko Bertović] wondered the same thing and he built an Arduino with a single button and a display. After doing some obvious things (like a counter or stopwatch) he decided to make a calculator for his latest Volos Projects video.
You can find the source code online and he used a library from GitHub to handle the reaction to single presses, double presses, and long presses. Is it ideal? Probably not. But if you only have a limited amount of space or pins, it can make the difference between a feasible project and one you can’t finish.
His original projects also included a Flappy Bird clone. The OLED display is only 64×48 so that’s not a lot of room. The packaging of the tiny Arduino, the battery, and the display in a good looking case, was pretty impressive. So the device might be usable for something.
Of course, the library will work with any program and there’s no reason you can’t have more than one button and simply multiply their functions with the same strategy. There’s a sample on GitHub that shows how you can create two OneButton objects connected to different hardware devices.
By the way, the little box may have only one button, but it also has a power switch. Turns out, you can use it as an input in certain circumstances. If the OLED display strikes you as too luxurious, try the DUO BINARY.
When building projects with a simple goal in mind, it’s not unheard of for us to add more and more switches, buttons, and complexity as the project goes through its initial prototyping stages. Feature creep like this tends to result in a tangled mess rather than a usable project. With enough focus, though, it’s possible to recognize when it’s happening and keep to the original plans. On the other hand, this single-button project with more than one use seems to be the opposite of feature creep. (YouTube, embedded below.)
[Danko]’s project has one goal: be as useful as possible while only using a single button and a tiny screen. Right now the small handheld device can be used as a stopwatch, a counter, and can even play a rudimentary version of flappy bird. It uses an Arduino Pro Mini, a 64×48 OLED screen running on I2C, and has a miniscule 100 mAh 3.7V battery to power everything. The video is worth watching if you’ve never worked with this small of a screen before, too.
Getting three functions out of a device with only one button is a pretty impressive feat, and if you can think of any other ways of getting more usefulness out of something like this be sure to leave it in the comments below. [Danko] is no stranger to simple projects with tiny screens, either. We recently featured his homebrew Arduino calculator that uses an even smaller screen.
If you’ve got a SEGA Dreamcast kicking around in a closet somewhere, and you still have the underutilized add-on Visual Memory Unit (VMU), you’re in for a treat today. If not, but you enjoy incredibly detailed hacks into the depths of slightly aged silicon, you’ll be even more excited. Because [Dmitry Grinberg] has a VMU hack that will awe you with its completeness. With all the bits in place, the hacking tally is a new MAME emulator, an IDA plugin, a never-before ROM dump, and an emulator for an ARM chip that doesn’t exist, running Flappy Bird. All in a month’s work!
The VMU was a Dreamcast add-on that primarily stored game data in its flash memory, but it also had a small LCD display, a D-pad, and inter-VMU communications functions. It also had room for a standalone game which could interact with the main Dreamcast games in limited ways. [Dmitry] wanted to see what else he could do with it. Basically everything.
We can’t do this hack justice in a short write-up, but the outline is that he starts out with the datasheet for the VMU’s CPU, and goes looking for interesting instructions. Then he started reverse engineering the ROM that comes with the SDK, which was only trivially obfuscated. Along the way, he wrote his own IDA plugin for the chip. Discovery of two ROP gadgets allowed him to dump the ROM to flash, where it could be easily read out. Those of you in the VMU community will appreciate the first-ever ROM dump.
On to doing something useful with the device! [Dmitry]’s definition of useful is to have it emulate a modern CPU so that it’s a lot easier to program for. Of course, nobody writes an emulator for modern hardware directly on obsolete hardware — you emulate the obsolete hardware on your laptop to get a debug environment first. So [Dmitry] ported the emulator for the VMU’s CPU that he found in MAME from C++ to C (for reasons that we understand) and customized it for the VMU’s hardware.
Within the emulated VMU, [Dmitry] then wrote the ARM Cortex emulator that it would soon run. But what ARM Cortex to emulate? The Cortex-M0 would have been good enough, but it lacked some instructions that [Dmitry] liked, so he ended up writing an emulator of the not-available-in-silicon Cortex-M23, which had the features he wanted. Load up the Cortex emulator in the VMU, and you can write games for it in C. [Dmitry] provides two demos, naturally: a Mandlebrot set grapher, and Flappy Bird.
Amazed? Yeah, we were as well. But then this is the same guy emulated an ARM chip on the AVR architecture, just to run Linux on an ATMega1284p.
Back in 2014 [Johan] decided to celebrate BASIC’s 30 50 year anniversary by writing his own BASIC interpreter. Now, a few years later, he says he feels he has hit a certain milestone: he can play Flappy Bird, written in his own version of BASIC, running on his own home-built computer, the BASIC-1.
Inside the BASIC-1 is an Atmel XMega128A4, a keyboard from a broken Commodore 64, a joystick port, a serial to TV out adapter, and an SD card adapter for program storage. An attractively laser-cut enclosure with kerf bends houses the keyboard and hardware. The BASIC-1 boots into BASIC just like many of its home computer counterparts from the 80s.
