While the “M” in MIDI stands for “musical”, it’s possible to use this standard for other things as well. [s-ol] has been working on a VJ setup (mixing video instead of music) using various potentiometer-based hardware and MIDI to interface everything together. After becoming frustrated with drift in the potentiometers, he set out to outfit the entire rig with custom-built encoders.
[s-ol] designed the rotary-encoder based boards around an FPGA. It monitors the encoder for changes, controls eight RGB LEDs per knob, and even does capacitive touch sensing on the aluminum knob itself. The FPGA communicates via SPI with an Arduino master controller which communicates to a PC using a serial interface. This is [s-ol]’s first time diving into an FPGA project and it looks like he hit it out of the park!.
Even if you’re not mixing video or music, these encoders might be useful to any project where a standard analog potentiometer isn’t accurate or precise enough, or if you just need something that can dial into a specific value quickly. Potentiometers fall short in many different ways, but if you don’t want to replace them you might modify potentiometers to suit your purposes.
Continue reading “Upgrading A MIDI Controller With An FPGA”
Hackaday Editors Mike Szczys and Elliot Williams cover the most interesting hacks over the past week. So much talk of putting computers in touch with our brains has us skeptical on both tech and timeline. We celebrated the 40th Anniversary of the Walkman, but the headphones are the real star. Plus, Verilog isn’t just for FPGAs, you can synthesize 7400 circuits too! Elliot is enamored of an additive/subtractive printing process that uses particle board, and we discuss a couple of takes on hybrid-powered drones.
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!
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Continue reading “Hackaday Podcast 028: Brain Skepticism Turned Up To 11, Web Browsing In ’69, Verilog For 7400 Logic, 3D Printing In Particle Board”
Breathing LEDs are an attractive adornment on many electronic devices. These days they’re typically controlled by software but of course there were fading effects back in the days of analog too. [Pepijn de Vos] mixes a little of the new and the old by building a hardware-based fader from a Verilog design and even too the time to explain the process in depth.
Rather than using a microcontroller and software, [Pepijn] wrote the logic required to make the LED “breathe” in the hardware description language, Verilog. You may be familiar with this for FPGAs, but using it to plan out a build with logic chips is just as apt a use. The Verilog was synthesized into a circuit using 74-series logic chips, with the help of work by [Dan Ravensloft] who has made a library for the Yosys Open Synthesis Suite. With the addition of a basic clock circuit, the LED is made to breathe and the rate can be controlled by changing the clock speed.
It’s a fun way to experiment with both Verilog and old-school logic, albeit one that may not scale well. An interesting side note from the Twitter thread, [Dan] estimates that with current settings the PicoRV32 CPU would require over 2000 chips to build. Regardless, it’s an interesting tool and one that likely has further scope for experimentation.
First patented by Apple way back in 2002, the breathing LED has been a popular project for those learning electronics. We’ve even seen it on motorbikes. Video after the break.
Continue reading “Breathing LED Done With Raw Logic Synthesized From A Verilog Design”
With the wide availability of Raspberry Pi hardware and pre-baked Linux distros with emulators ready to go, making a retro handheld is easier than ever. Emulation isn’t the only way to go about playing old games however. [Wenting Zhang] decided to instead recreate the Nintendo Game Boy in Verilog, and has documented the effort.
The project runs on a Spartan 6 FPGA. [Wenting] first developed the hardware to use a DualShock controller for input, and output video to a regular LCD monitor. However, work is now underway to produce a handheld VerilogBoy. This will feature a 320×320 LCD screen, with pixels being quadrupled from the original Game Boy 160×144 resolution, with some pixels to spare. [Wenting] is also looking at porting the code to some Pano Logic units, which we’ve discussed before. The thin clients pack FPGA hardware and lots of IO ports that make them perfect for such a project.
Code is available on Github for the curious tinkerers out there. While there are easier ways to play old handheld games, the amount of learning value of such a project should not be underestimated. We’ve seen FPGAs used for other Nintendo hijinx, too – like this NES cart that packs some serious muscle. Video after the break.
Continue reading “Game Boy Recreated In Verilog”
Reinforcement learning has been a hot-button area of research into artificial intelligence. This is a method where software agents make decisions and refine these over time based on analyzing resulting outcomes. [Kamil Rocki] had been exploring this field, but needed some more powerful tools. As it turned out, a cluster of emulated Game Boys running at a billion FPS was just the ticket.
The trick to efficient development of reinforcement learning systems is to be able to run things quickly. If it takes an AI one thousand attempts to clear level 1 of Super Mario Bros., you’d better hope you’re not running that in real time. [Kamil] started by coding a Game Boy emulator in C. By then implementing it in Verilog, [Kamil] was able to create a cluster of emulated Game Boys that enabled games to be run at breakneck speed, greatly speeding the training and development process.
[Kamil] goes into detail about how the work came to revolve around the Game Boy platform. After initial work with the Atari 2600, which is somewhat of a defacto standard in RL circles, [Kamil] began to explore further. It was desired to have an environment with a well-documented CPU, a simple display to cut down on the preprocessing required, and a wide selection of games.
The goal of the project is to allow [Kamil] to explore the transfer of knowledge from one game to another in RL systems. The aim is to determine whether for an AI, skills at Metroid can help in Prince of Persia, for example. This is arguably true for human players, but it remains to be seen if this can be carried over for RL systems.
It’s rather advanced work, on both a hardware emulation level and in terms of AI research. Similar work has been done, training a computer to play Super Mario through monitoring score and world values. We can’t wait to see where this research leads in years to come.
Classic battles: PC vs Mac, Emacs vs Vi, Tastes Great vs Less Filling, and certainly one that we debate around the Hackaday watercooler: command line or IDE? There’s something to be said for using good old command line tools, and even if you like to configure your favorite editor to be nearly an IDE, at least it is one you are familiar with and presumably leverage over several different uses.
Most commercial FPGA tools come with a heavy-weight IDE. The open source tools for Lattice (IceStorm) typically is driven by the command line or a makefile. Until now. [Rochus-Keller] released VerilogCreator which is a plugin for QtCreator.
We were impressed because as IDEs go, QtCreator is both useful and lightweight, two things that don’t go together for many similar tools. [FPGAwars] has had an IDE based on Atom (apio-ide) although it hasn’t been updated in nearly a year. IceStudio sees more updates, of course, but it isn’t so much an IDE as a GUI-based code builder.
[Rochus-Keller] says there’s more to come. However, even at this early stage the IDE does syntax coloring, tooltips, inline messages, and can analyze source code allowing you to cross-reference symbols as you’d expect. There are configurations for Icarus to do simulations or you can use Verilator or Yosys — the synthesizer behind IceStorm. It appears it can also interact with Tcl-based workflows like those used by most FPGA vendor IDEs.
There’s quite a bit still on the to-do list, so we are excited to see where this is going. QtCreator isn’t hard to learn and it doesn’t’ feel as bloated as some of the big IDEs like Eclipse. If you want a quick introduction to QtCreator, we did that already. If you want to draw boxes instead of writing Verilog directly, try IceStudio.
If you have a thing for old game development — things like the Atari 2600 or similar period arcade games — you might already know about the 8bitworkshop IDE. There you can develop code in your browser for those platforms. In a recent blog post, the site announced you can now also do FPGA development in the IDE.
According to the site:
Most computers are fast enough to render a game at 60 Hz, which requires simulating Verilog at almost 5 million ticks per second.
To activate Verilog, you need to select the hamburger menu to the top left, select Platform, and then under Hardware, check Verilog. What makes this different from, say, EDA Playground, is that the output can be waveforms or the output to a virtual TV monitor. For example, here’s one of the examples:
The Verilog code is generating horizontal and vertical sync along with an RGB output and the results appear on the monitor to the right. There is a handle at the bottom of the screen. If you drag it up you will see the logic analyzer output. Drag it down and you’ll see the screen again. The examples include an 8-bit and 16-bit CPU, and example games that can even read the mouse.
Honestly, we don’t think anyone would suggest using Verilog to write in-browser games. That isn’t really the point here. However, if you are trying to learn Verilog, it is great fun to be able to produce something other than just abstract waveforms from simulation. The only downside is that to move to a real piece of hardware, you’d need to duplicate the interfaces provided by the IDE. That would not be very hard, and — of course — if you are just using it to learn you can try a different project for the real world.
If you need help getting going in Verilog, we have a series of boot camps that can help. Those tutorials use EDA Playground, but they’d probably work here, too. If you try them in the IDE, be sure to let us know your experience.