MIDI-Controlled Digital Synthesizer

4bitsynth is 4 bit MIDI-controlled digital synthesizer inspired by the NES. The project is built around Atmel AVR ATMega48 The digital output is put through an R-2R resistor ladder to get the analog waveform. It has three type output : Square wave, Triangle wave and noise.

Project Features Detail :
Triangle

* One volume (uses up/down counter)
* Pitch sweep (up/down, optional looping)
* Standard pitch bend
* Fine pitch bend


Square

* Three duty cycles: 12.5%, 25%, 50%
* Volume decay (optional looping)
* Pitch sweep (up/down, optional looping)
* Standard Pitch bend
* Fine pitch bend

Noise

* Two modes: 93-bit and 32k (think NES)
* Volume decay (optional looping)
* Pitch sweep (up/down, optional looping)
* Standard pitch bend
* Fine pitch bend
more

Optical String Tuning Tool, AVR AtMega8

Stimmmopped is AVR ATmega8-based project that will assists you in tuning your string instrument to a given tone. It utilizes the stroboscopic effect to give feedback about the adjustment of your instrument. When the frequency that you chose has tone then the two LEDs on the board blink. Two lines are projected at a fixed position on the string when the string vibrates with the correct frequency. If frequencies don't match, the lines appear to be blinking or moving to the observer's eye. The moving or blinking effect decreases with decreasing difference between the two frequencies.

"The project has two switches to choose the tone and instrument. Switch S1 toggles the current mode of the menu, which is either "choose instrument" or "choose tone". The 7-segment display displays the current selection. In the instrument selection mode, the display is lit up a bit brighter. Switch number two (S2) selects the tone or instrument in the given mode." said Madex (Martin), the designer.

Source Code And Layout

How to Find the Most Memory taking process in Ubuntu Linux

Some Times system administrators need to kill the memory eater process. When your system become slower, check the following command and find the memory eater.


Open a terminal and Type the following command

#ps aux | sort -nrk 4 | head