PWM_LED_SPI_75595.ino

/*
PWM  mit Shift Baustein 74595
Speichere dies als
PWM_LED_SPI_75595.ino
und öffne es mit der SKETCH Oberfläche
*/

 //#include <util/delay.h>
#include <avr\wdt.h>

#define  DEF_OCR2A_COMP_VALUE  54
#define TWO_CYCLES() __asm__ __volatile__( "rjmp 1f\n 1:" ) // 2 cycles

#ifndef SPI_SHIFTOUT_74_595_HEADER
  #define SPI_SHIFTOUT_74_595_HEADER

//SPI_BUS ATMega328p
#define SCK_PIN   PB5
#define MISO_PIN  PB4
#define MOSI_PIN  PB3
#define SS_PIN    PB2

#define SPI_DDRX                DDRB
#define SPI_PORTX               PORTB
#define TTL74595_DS_PIN_NR      MOSI_PIN  //DATA
#define TTL74595_SH_CP_PIN_NR   SCK_PIN //SCK
#define TTL74595_ST_CP_PIN_NR   SS_PIN //RCK

//PINS
#define DS_TTL74595     (1<< TTL74595_DS_PIN_NR  )   // DATA
#define SH_CP_TTL74595  (1<< TTL74595_SH_CP_PIN_NR ) //SCK
#define ST_CP_TTL74595  (1<< TTL74595_ST_CP_PIN_NR )  // Store / RCK

#define OUT_TTL74595_RCK_HIGH() (SPI_PORTX |= ST_CP_TTL74595)
#define OUT_TTL74595_RCK_LOW()  (SPI_PORTX &= ~ST_CP_TTL74595)

#endif //SPI_SHIFTOUT_74_595_HEADER

// *************************************************************************************
//GLOBAL
volatile uint8_t gu8LedPWM[8];
// *************************************************************************************

// *******************************
void SPI_SlaveInit(void)
// *******************************
{
/* Set MISO output, all others input */
PRR &= ~(1<<PRSPI);  //POWER ON SPI
/* Enable SPI */
//SPCR = (1<<SPE)|(1<<MSTR)|(1<<SPR0); //fosc/4
SPI_DDRX |= DS_TTL74595 | SH_CP_TTL74595  | ST_CP_TTL74595;
}

// *********************************************
ISR( SPI_STC_vect  )  //SPI Transfer complete
// *********************************************
{
OUT_TTL74595_RCK_HIGH(); // Latch Data to Output
__asm__ __volatile__( "rjmp 1f\n 1:" ); // 2 cycles
OUT_TTL74595_RCK_LOW();
};

// **************************************
void SPI_TTL74595( uint8_t u8Val )  //uint16_t uint32_t
// **************************************
{
  //S:174
  SPDR = ~u8Val; // Mache Komplement, weil LED_ LIEGET AN PLUS
  SPCR = (1<<SPE)|(1<<MSTR)|(1<<SPR0) | (1<<SPIE); //fosc/4  + SPI Interrupt
};


//Für Test mit Oszi:
void ToogleBit(void)
{
  DDRC |= 0x01;
  PORTC |= 0x01;
    //TWO_CYCLES();
  _delay_us(2);
  PORTC &= ~0x01;
}

// ****************************************************************
  //ISR( TIMER2_OVF_vect )
ISR( TIMER2_COMPA_vect )
// *******************************************************************
{
 volatile uint8_t u8NN;
  //uint8_t u8Sreg = SREG;
 volatile static uint8_t u8Periode=0;
 volatile static uint8_t u8Val=0xFF;
  if( !u8Periode  ) //== 0
    {
    u8Val=0xFF;
    }
  else
    {
    for( u8NN=0; u8NN < 8; u8NN++)
      {//Clear passenden OutBit if Match
       if( gu8LedPWM[u8NN] == u8Periode )
        {
        u8Val &= ~(1 << u8NN);
        };
      }
    };
  //S:174
  SPDR = ~u8Val; // Mache Komplement, weil LED_ LIEGET AN PLUS
  SPCR = (1<<SPE) | (1<<MSTR) | (1<<SPR0) | (1<<SPIE); //fosc/4  + SPI Interrupt
 //SPI_TTL74595(u8Val);
 u8Periode++; //u8 Interrupt Durchlaufzähler mit 0
 //SREG = u8Sreg;
};

// ************************
int main(void)
// ************************
{  // put your main code here, to run repeatedly:
uint8_t u8NN;
uint8_t u8FF;
uint8_t u8MemVal;

//wdt_enable(WDTO_500MS); //WatchDog ENABLE
wdt_disable();
for( u8NN=0; u8NN < 8; u8NN++)
  {
    gu8LedPWM[u8NN] = u8NN *32;
  };

SPI_SlaveInit();

  TCNT2 = 0;
//COMP SECTION
  OCR2A =  DEF_OCR2A_COMP_VALUE;  //?? >50%
  TCCR2A= (1<<WGM21); //CTC Mode
  TIMSK2 = (1 << OCIE2A);
 TCCR2B = (1 << CS21); // CLOCK /8

while(1)
  {
//ToogleBit();  // Trigger für Test Oszi
//wdt_reset();  //WATCHDOG!

//Erzeuge 8 Sinus Modulationen für 8 PWM Bits mit Phasenabstand 265/8 =32
  u8NN++;  //Phasenschieber
  for(u8FF=0; u8FF < 8; u8FF++)
    {
      u8MemVal = 128 + 127*sin(2*M_PI*(((uint8_t)(u8NN+(u8FF*32)))/256.0));
     //Damits schnell geht ohne Rechnung
     cli();
     gu8LedPWM[u8FF] = u8MemVal;
     //gu8LedPWM[u8FF] = 70;
     sei();
    };
  _delay_ms(5);
  };
 };