I checked my suitcase full of components to find that there were plenty of parts which I had bought and never used. I had Atmega32, DACs, PT2399 digital delay chip, ssm2164 VCA chip... so I had to do something with all that, what? definately something noisy!!!
So far my thought is doing a 6 voiced paraphonic synth with square wave oscillators and frequency dividers to get an organ type sound but with a cool 24dB/oct VCF to give it a cool synth sound. Well, that is the idea, we will see what I come up with, experimentation is the key this time. The name: Kula6, why? why not...
Anyway, so I started with the power supply: a bipolar power supply with +/- 12V and 5V outputs and the basic circuitry for the Atmega32. I added an LED on one of the Atmega outputs for testing the usual blinky LED example. Schematic here:
And the code for the blinky LED, from hackday:
#include <avr/io.h>
#include <avr/interrupt.h>
int main(void)
{
//Setup the clock
cli(); //Disable global interrupts
TCCR1B |= 1<<CS11 | 1<<CS10; //Divide by 64
OCR1A = 15624; //Count 15624 cycles for 1 second interrupt
TCCR1B |= 1<<WGM12; //Put Timer/Counter1 in CTC mode
TIMSK |= 1<<OCIE1A; //enable timer compare interrupt
sei(); //Enable global interrupts
//Setup the I/O for the LED
DDRC |= (1<<0); //Set PortC Pin0 as an output
PORTC |= (1<<0); //Set PortC Pin0 high to turn on LED
while(1) { } //Loop forever, interrupts do the rest
}
ISR(TIMER1_COMPA_vect) //Interrupt Service Routine
{
PORTC ^= (1<<0); //Use xor to toggle the LED
}
And this is how my prototype board looks like:
