Tag Archives: Jan Cumpelik

ATmega328 drives this rockin’ Lunchbeat sequencer

A Maker by the name of Jan Cumpelik has designed a rockin’ breadboard sequencer aptly dubbed “Lunchbeat.”

Powered by Atmel’s stalwart ATmega328, the microcontroller (MCU) accepts inputs from the neat row of 10k trimpots as well as a series of tactile switches. Feedback is provided by a row of 8 LEDs – 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,” writes HackADay’s Mike Szczys.

“[Below] 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.”

As previously discussed on Bits & Pieces, Atmel’s ATmega328 is a a high-performance 8-bit AVR RISC-based microcontroller that boasts 32KB ISP flash memory with read-while-write capabilities, 1KB EEPROM, 2KB SRAM, 23 general purpose I/O lines, 32 general purpose working registers and three flexible timer/counters with compare modes.

Additional key specs include internal and external interrupts, serial programmable USART, a byte-oriented 2-wire serial interface, SPI serial port, 6-channel 10-bit A/D converter (8-channels in TQFP and QFN/MLF packages), a programmable watchdog timer with internal oscillator and five software selectable power saving modes. Operating between 1.8-5.5 volts, the  ATmega328 executes powerful instructions in a single clock cycle Рachieving throughputs approaching 1 MIPS per MHz Рneatly balancing power consumption with processing speed.

Interested in learning more? You can read more about the ATmega328 on Atmel’s website.