ATtiny13

Memo fact sheet

• Code : 1024 Bytes / EEPROM : 64 Bytes / RAM : 64 Bytes
• It has 4 ADC- Analog to Digital Converter !
• Default speed : internal oscillator 9.6 MHz, alternate is 4.8Mhz. The internal oscillator has always proven to be very imprecise, so adjust it, tweak your timings or use an external crystal.
• Homepage http://www.atmel.com/devices/attiny13.aspx

Links

• My Attiny13 codes on github, with samples of different techniques (Serial, PWM, ...)
• The bases, with samples, and on Wikispaces : http://avrbasiccode.wikispaces.com/
• It's ATtiny45 but maybe compliant ? Have to read further : http://kehribar.me/projects/Little-Wire/

Samples

Blink

/* includes */
#include "avr/io.h"
#include "util/delay.h"
 
/*
 main function
*/
int main(void) {
 
    /*factory settings is to divide internal clock 8MHz by 8.
    don't, and just run at 8 MHz (set the clock divider to 1 so no effect) */
    CLKPR = (1 < < CLKPCE);
    CLKPR = 0; /* Divide by 1 */
 
    /* port B pins 0-5 go OUTPUT */
    DDRB = 0xFF;
 
    while (1==1){
        /*all on*/
        PORTB = 0xFF;
 
        /*wait a little*/
        _delay_ms(500);
 
        /*all off*/
        PORTB = 0x00;
 
        /*wait again*/
        _delay_ms(200);
 
    }
}

PWM

// includes
#include 
#include 
#include 
 
//
// main function
//
int main(void) {
 
    //factory settings is to divide internal clock 8MHz by 8.
    //don't, and just run at 8 MHz (set the clock divider to 1 so no effect)
    CLKPR = (1<<CLKPCE);
    CLKPR = 0; // Divide by 1 
 
    //port B pins 0-5 go OUTPUT
    DDRB = 0xFF;
 
//PWM : Use this line...
TCCR0A |= ((1 << COM0A1) | (1 << COM0A0) // COM0A1 - COM0A0 (Set OC0A on Compare Match, clear OC0A at TOP)
 | (1 << WGM01) | (1 << WGM00)); // WGM01 - WGM00 (set fast PWM)
 
//...or those lines. No (noticeable) difference.
    /* Set Fast PWM mode. */
    //TCCR0A |= (1<
    /* Clear 0C0A on compare. */
    //TCCR0A |= (1<
 
 
    /* Start timer, no prescaling. */
    TCCR0B |= (1<<CS00);
    //initial PWM value is 0
    OCR0A = 0x00;
 
    while (1==1){
        for (int i=0; i < 255; i %20%20){
            OCR0A = i;
            _delay_ms(5);
        }
 
        for (int i=0; i < 255; i %20%20){
            OCR0A = 255-i;
            _delay_ms(5);
        }
 
    }
}

Soft PWM on 3%20 pins

• Starting at current turn==0 when you light everybody on (turn pins HIGH).
• When the current turn (a byte that keeps on rolling between 0 and 255) reaches the desired value, turn that pin LOW.
• At each turn pause a little time (△) for the POV and increment current turn

    uint8_t vRGBCurrentRound = 0;
    while(1)
    {
        //todo : put this in an interrupt?
        if (vRGBCurrentRound == 0){
            /*
            //make pins B0-2 high
            PORTB = 
                (1 << PORTB0) 
                | (1 << PORTB1)
                | (1 << PORTB2)
                ;
            */
 
            PORTB = 0x00;
            if (mRGB[0] > 0)
                PORTB |= (1 << PORTB0);
            if (mRGB[1] > 0)
                PORTB |= (1 << PORTB1);
            if (mRGB[2] > 0)
                PORTB |= (1 << PORTB2);        
        }
 
 
        if (vRGBCurrentRound == mRGB[0] && vRGBCurrentRound != 255){
            PORTB &= ~(1 << PORTB0);
        }
 
        if (vRGBCurrentRound == mRGB[1] && vRGBCurrentRound != 255){
            PORTB &= ~(1 << PORTB1);
        }
 
        if (vRGBCurrentRound == mRGB[2] && vRGBCurrentRound != 255){
            PORTB &= ~(1 << PORTB2);
        }
 
        //and the POV
        _delay_us(50);
        vRGBCurrentRound%20%20;
    }