Way back when, home computers and consoles didn’t have the RAM or storage space for full-length recorded audio tracks. Instead, a variety of techniques were used to synthesize music on the fly. The SNES was no exception, using the SPC700 Wavetable Synthesis chip to bust out the tunes. [Foxchild] wanted to use this chip as a standalone synthesizer, but didn’t want to hack up a console to do so. Thus, the SNES Drone was born!
Instead of gutting the console for the juicy chips inside, à la most SID based builds, the SNES Drone takes a different approach. It consists of a cartridge which interfaces with a stock SNES console, making the install easy and non-invasive.
The build is in an alpha state, with the oscillators in the SNES generating continuous tones, with frequency and volume controlled by potentiometers mounted on the cartridge. Having physical controls on the cartridge makes the build feel more like a real synth, and promises to look awesome on stage for a chiptune performance.
Chiptunes are the fantastic, bleeping musical renditions of the soundchips of retro consoles past. Performers of the art overwhelmingly favour the various flavours of Game Boy, though there are those who work with such varied machines as the Commodore 64, Sega Genesis, and the Nintendo Entertainment System. A little more off the beaten track in the chiptune scene is the Super Nintendo, but [kevtris] has struck out and built a chiptune player for SNES-based music.
The heavy lifting is handled by an FPGA, which emulates the SNES’s S-SMP sound processor, and handles loading the music from the SPC-format files. Being chiptunes, these files store both the instrument data as well as the note data for the music. Audio output is clean and crisp, as heard in the test video.
Case design is where this project really shines. Laser cut clear acrylic is combined with a bright LCD character display and some LEDs which create an effect not unlike a glowing magical block from your 90s platformer of choice. It’s combined with some slick capacitive buttons that avoid the need to drill holes for bulky traditional buttons. [kevtris] goes through the case design, showing how it all fits together with a combination of screws and standoffs. Being built out of a series of essentially 2D slices, the case is stacked up one layer at a time.
What really stands out about this project is the fit and finish. There’s plenty of microcontroller and FPGA projects out there that can hum out a tune, but the attention to detail paid to the case design and the neatly laid out PCB really add polish to a project like this. For a different take, why not check out this chiptune player built around a Raspberry Pi?