Todd E. Stidham's Open Source BuzzKill Board Drives This Panicky Speaking Voltmeter
Speech synthesis delivers an eyes-off readout of a circuit's voltage — and as the volts rise, so too does a sense of panic.
Maker Todd E. Stidham has found a new use for a compact sound effect board developed for use with microcontrollers: creating a speaking voltmeter that gives the impression of growing panic the higher the measured voltage gets.
"Since I developed my BuzzKill board, I've basically just kept it mounted on an Arduino," Stidham explains. "I was doing a completely separate project where I needed some sensor readings, using an LCD for output. And it suddenly dawned on me that, since the BuzzKill board was already there, it could speak the results as well for hardly any extra code. So I quickly cobbled together a demo."
The BuzzKill is Stidham's open source sound effect generator — not an audio playback board, he notes, but a device that dynamically generates sounds from user-supplied parameters. "BuzzKill is most useful as a peripheral for a microcontroller," the maker explains. "Using either an I2C or SPI interface, a controller can send commands to produce an infinite variety of sounds. Essentially, BuzzKill acts as a compact musical instrument producing sounds on demand. It contains a full-featured additive synthesizer, capable of emulating an assortment of instrument sounds or creating totally new ones."
Rather than music, though, Stidham's latest demo of the board generates synthesized speech reading out a voltage of a connected circuit. As the voltage rises, so too does the pitch of the voice — giving the impression of growing panic from the gadget.
The source code for the project is available in Stidham's Reddit post, while the BuzzKill hardware, firmware source code, and example projects are all available on GitHub under the permissive MIT license.