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2017-12-12 10:19:50 +01:00
//#define ARDUINO_AVR_PRO 1
#define ORANGE_TX 1
#include <stdlib.h>
#include <string.h>
#include <avr/interrupt.h>
#define yield()
#define clockCyclesPerMicrosecond() ( F_CPU / 1000000L )
#define clockCyclesToMicroseconds(a) ( (a) / clockCyclesPerMicrosecond() )
// the prescaler is set so that timer0 ticks every 64 clock cycles, and the
// the overflow handler is called every 256 ticks.
#define MICROSECONDS_PER_TIMER0_OVERFLOW (clockCyclesToMicroseconds(64 * 256))
// the whole number of milliseconds per timer0 overflow
#define MILLIS_INC (MICROSECONDS_PER_TIMER0_OVERFLOW / 1000)
// the fractional number of milliseconds per timer0 overflow. we shift right
// by three to fit these numbers into a byte. (for the clock speeds we care
// about - 8 and 16 MHz - this doesn't lose precision.)
#define FRACT_INC ((MICROSECONDS_PER_TIMER0_OVERFLOW % 1000) >> 3)
#define FRACT_MAX (1000 >> 3)
#ifndef cbi
#define cbi(sfr, bit) (_SFR_BYTE(sfr) &= ~_BV(bit))
#endif
#ifndef sbi
#define sbi(sfr, bit) (_SFR_BYTE(sfr) |= _BV(bit))
#endif
void init()
{
// this needs to be called before setup() or some functions won't
// work there
// Enable external oscillator (16MHz)
OSC.XOSCCTRL = OSC_FRQRANGE_12TO16_gc | OSC_XOSCSEL_XTAL_256CLK_gc ;
OSC.CTRL |= OSC_XOSCEN_bm ;
while( ( OSC.STATUS & OSC_XOSCRDY_bm ) == 0 )
/* wait */ ;
// Enable PLL (*2 = 32MHz)
OSC.PLLCTRL = OSC_PLLSRC_XOSC_gc | 2 ;
OSC.CTRL |= OSC_PLLEN_bm ;
while( ( OSC.STATUS & OSC_PLLRDY_bm ) == 0 )
/* wait */ ;
// Switch to PLL clock
CPU_CCP = 0xD8 ;
CLK.CTRL = CLK_SCLKSEL_RC2M_gc ;
CPU_CCP = 0xD8 ;
CLK.CTRL = CLK_SCLKSEL_PLL_gc ;
PMIC.CTRL = 7 ; // Enable all interrupt levels
sei();
#if defined(ADCSRA)
// set a2d prescale factor to 128
// 16 MHz / 128 = 125 KHz, inside the desired 50-200 KHz range.
// XXX: this will not work properly for other clock speeds, and
// this code should use F_CPU to determine the prescale factor.
sbi(ADCSRA, ADPS2);
sbi(ADCSRA, ADPS1);
sbi(ADCSRA, ADPS0);
// enable a2d conversions
sbi(ADCSRA, ADEN);
#endif
// the bootloader connects pins 0 and 1 to the USART; disconnect them
// here so they can be used as normal digital i/o; they will be
// reconnected in Serial.begin()
#if defined(UCSRB)
UCSRB = 0;
#elif defined(UCSR0B)
UCSR0B = 0;
#endif
// Dip Switch inputs
PORTA.DIRCLR = 0xFF ;
PORTA.PIN0CTRL = 0x18 ;
PORTA.PIN1CTRL = 0x18 ;
PORTA.PIN2CTRL = 0x18 ;
PORTA.PIN3CTRL = 0x18 ;
PORTA.PIN4CTRL = 0x18 ;
PORTA.PIN5CTRL = 0x18 ;
PORTA.PIN6CTRL = 0x18 ;
PORTA.PIN7CTRL = 0x18 ;
}