/* adc.c */ /* n.avr.adc - AVR ADC Module. {{{ * * Copyright (C) 2005 Thomas Burg * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * Contact : * Email: * }}} */ #include "adc.h" #include #include /* Tested AVR check. */ #if defined (__AVR_ATmega8__) #elif defined (__AVR_ATmega8535__) #elif defined (__AVR_ATmega128__) #else # warning "adc: not tested on this chip." #endif /* +AutoDec */ /* -AutoDec */ /* CONF: * 0x40 AVCC with external capacitor at AREF pin * 0xC0 Internal 2.56V Voltage Reference with external capacitor at AREF * pin */ #define CONF 0xC0 /** Initialise adc. */ void adc_init (void) { ADMUX = CONF; #if defined (__AVR_ATmega8535__) ADCSRA = ADEN | 0x7; #else ADCSR = ADEN | 0x7; #endif } /** Choose and start mesure on adc line */ void adc_start (uint8_t d) { // Choose adc ADMUX = CONF | ( d & 0x07); /* ADEN active l'adc * ADSC demarre la mesure */ #if defined (__AVR_ATmega8535__) ADCSRA |= ADSC; #else ADCSR |= ADSC; #endif } /** check on finish mesure */ uint8_t adc_checkf (void) { // return != than zero when convertion is complete #if defined (__AVR_ATmega8535__) return ADCSRA & ADIF; #else return ADCSR & ADIF; #endif } /** Read mesure */ uint16_t adc_read (void) { #if defined (__AVR_ATmega8535__) ADCSRA &= ~ADIF; #else ADCSR &= ~ADIF; #endif return ADCW; }