Having tackled the AVR Timers and Interrupts to make a Noise Chip for the BOSS DR-110 in the article Noisey chips, I now feel confident to take on and answer this question on Stack Exchange, Program an ATtiny13 as an audio oscillator with variable frequency and pulse-width. The added bonus is that it can be used to create an Atari punk Console (APC)-esque device.
Initially I will use an ATmega328…
Just for the hell of it, I wondered if it was possible to substitute the 555 timers in an Atari Punk Console (APC) with some other component, or components.
After seeing some Schmitt-trigger inverters (CD40106) used in oscillator circuits, see Swingers, I thought that I would come up with an alternative design.
A friend of mine sent me details of the 555 Noisemusick kit, which, while it looks like an Atari Punk Console (APC) – see Atari Punx… – it is essentially two astable multivibrators, with the first providing a CV input to the second, and with additional IR sensors and touch pads (rather than an astable followed by a monostable, which is what the APC is).
Following on from Atari Punx…, which was my first foray into the world of electronic sound generation, it seemed that a sequencer is a very useful piece of additional kit. One can be easily made using a CD4017 decade counter (or CD4022 octal counter)… However, other ICs can be used, to provide additional functionality. For example, a CD4510/CD4516 BCD/Binary counter and a decoder or 16 channel multiplexer, such as a CD4028 or CD4067, can add up/down sequencing, pre-loading and other features.
Let’s take a look at all of these ICs as well as some others.
VCO, VCF and VCA circuits are also touched upon, be are covered more fully in Banging noises…
A friend of mine, Pavel, from the group Bang Sue Electrix, told me about the Atari Punk Sound generator. I’d never heard of it before, and I initially thought that he wanted to re-create either an old Atari VCS games console, or Atari 800 PC. When he showed me the Wikipedia – Atari Punk Console page, I realised that he was actually referring to a Stepped Tone Generator, formed from an astable square wave oscillator driving a monostable oscillator, (or – if you prefer – an astable multivibrator circuit triggering a monostable multivibrator circuit) which uses two 555 timers (or a single 556 timer IC)…
Reminiscent of vintage Atari video games, the synthesizer’s output is a characteristic Forrest Mims, a popular electronics author, published the original Atari Punk Console schematic for a “Sound Synthesizer” in Engineer’s Notebook: Integrated Circuit Applications and then a “Stepped Tone Generator” in Engineer’s Mini-Notebook: 555 Circuits. Kaustic Machines took the circuit and popularized their version as the “Atari Punk Console”.
This article looks at a the basic Atari Punk Console design, and then some variations, and improvements, upon the original design. Finally, it takes a look at replacing the 555 timers with some other multivibrators based around Schmitt triggers, BJT relaxation oscillator, and the oscillator taken from a Stylophone.
This article also takes a look at some unrelated 4069 musical projects… and some random projects including an Auduino and a theramin.