/* adc.avr.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: burg AT efrei DOT fr * }}} */ #include "common.h" #include "adc.h" #include "modules/utils/utils.h" #include "io.h" /* Tested AVR check. */ #if defined (__AVR_ATmega8__) #elif defined (__AVR_ATmega8535__) #elif defined (__AVR_ATmega128__) #elif defined (__AVR_ATmega64__) #elif defined (__AVR_ATmega16__) #else # warning "adc: not tested on this chip." #endif #if defined (__AVR_ATmega128__) #else /* If the ADCSRB register is not set, auto-trigger is equivalent to * free-running mode. */ # define ADFR ADATE #endif /* ADC configuration. */ /* REFS = 01: AVCC with external capacitor at AREF pin. * 11: Internal 2.56V Voltage Reference with external capacitor * at AREF pin. */ #define ADMUX_CFG (regv (REFS1, REFS0, ADLAR, MUX4, MUX3, MUX2, MUX1, MUX0, \ 1, 1, 0, 0, 0, 0, 0, 0)) #define ADCSR_CFG (regv (ADEN, ADSC, ADFR, ADIF, ADIE, ADPS2, ADPS1, ADPS0, \ 1, 0, 0, 1, 0, 0, 0, 0)) #define ADCSR_CFG_115200 7 /** Initialise ADC. */ void adc_init (void) { /* Low freq. */ ADCSR = ADCSR_CFG | ADCSR_CFG_115200; } /** Choose and start measure on ADC line. */ void adc_start (uint8_t c) { /* Choose ADC. */ ADMUX = ADMUX_CFG | (c & 0x07); /* Start measure. */ ADCSR |= _BV (ADSC); }