Breadboard Sequencer Does A Lot With Very Little Hardware


[Jan Cumpelik] squeezes a lot of performance out of very few components with his breadboard sequencer which he calls Lunchbeat. We really like his awesome breadboard which has a series of trenches perpendicular to the bus strips framing the long sides. All of our breadboards have just one trench down the middle. This, combined with his mad breadboard skills, results in a really clean prototype.

The chip nearest his hand is the ATmega328 which drives the sequencer. It takes inputs from that row of 10k trimpots as well as a series of tactile switches. Feedback is given with the row of eight LEDs. Those are driven from a 595 shift register to save pins on the microcontroller. The remaining chip is an OpAmp which works in conjunction with a 3-bit R2R ladder DAC to output audio. Turn your speakers down just a bit before taking in the demonstration below. There you will also find an image version of his schematic that we made for your convenience. It is only available as a PDF in the code repository he posted.



14 thoughts on “Breadboard Sequencer Does A Lot With Very Little Hardware

  1. I like the sound as well. And, that breadboard layout with the “vertical” trenches reminds me of the one in the middle of my RadioShack 300-in-one that I use mostly for the breadboard. Only real difference is the 300-in-one has just one bus at the bottom that is tied to the bat-, and the extreme top row, instead of a solid bus, is a tap from the internal 6 AA pack. (Mine has a tap on each cell, I’ve seen some versions of it that skip the 1.5v tap)

  2. Thanks for posting something useful and helpful for those of us with similar projects. After reading this I’m digging out the soundboard I built ages ago for some tweaks from this design.

    I’m always glad to see another project that isn’t connected to an Arduino..

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