--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/sanguino/cores/arduino/wiring_analog.c Thu Jul 07 12:23:34 2016 +0200 @@ -0,0 +1,282 @@ +/* + wiring_analog.c - analog input and output + Part of Arduino - http://www.arduino.cc/ + + Copyright (c) 2005-2006 David A. Mellis + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General + Public License along with this library; if not, write to the + Free Software Foundation, Inc., 59 Temple Place, Suite 330, + Boston, MA 02111-1307 USA + + Modified 28 September 2010 by Mark Sproul + + $Id: wiring.c 248 2007-02-03 15:36:30Z mellis $ +*/ + +#include "wiring_private.h" +#include "pins_arduino.h" + +uint8_t analog_reference = DEFAULT; + +void analogReference(uint8_t mode) +{ + // can't actually set the register here because the default setting + // will connect AVCC and the AREF pin, which would cause a short if + // there's something connected to AREF. + analog_reference = mode; +} + +int analogRead(uint8_t pin) +{ + uint8_t low, high; + +#if defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__) + if (pin >= 54) pin -= 54; // allow for channel or pin numbers +#elif defined(__AVR_ATmega32U4__) + if (pin >= 18) pin -= 18; // allow for channel or pin numbers +#elif defined(__AVR_ATmega1284__) || defined(__AVR_ATmega644p__) + if (pin >= 24) pin -= 24; // allow for channel or pin numbers +#else + if (pin >= 14) pin -= 14; // allow for channel or pin numbers +#endif + +#if defined(__AVR_ATmega32U4__) + pin = analogPinToChannel(pin); + ADCSRB = (ADCSRB & ~(1 << MUX5)) | (((pin >> 3) & 0x01) << MUX5); +#elif defined(ADCSRB) && defined(MUX5) + // the MUX5 bit of ADCSRB selects whether we're reading from channels + // 0 to 7 (MUX5 low) or 8 to 15 (MUX5 high). + ADCSRB = (ADCSRB & ~(1 << MUX5)) | (((pin >> 3) & 0x01) << MUX5); +#endif + + // set the analog reference (high two bits of ADMUX) and select the + // channel (low 4 bits). this also sets ADLAR (left-adjust result) + // to 0 (the default). +#if defined(ADMUX) + ADMUX = (analog_reference << 6) | (pin & 0x07); +#endif + + // without a delay, we seem to read from the wrong channel + //delay(1); + +#if defined(ADCSRA) && defined(ADCL) + // start the conversion + sbi(ADCSRA, ADSC); + + // ADSC is cleared when the conversion finishes + while (bit_is_set(ADCSRA, ADSC)); + + // we have to read ADCL first; doing so locks both ADCL + // and ADCH until ADCH is read. reading ADCL second would + // cause the results of each conversion to be discarded, + // as ADCL and ADCH would be locked when it completed. + low = ADCL; + high = ADCH; +#else + // we dont have an ADC, return 0 + low = 0; + high = 0; +#endif + + // combine the two bytes + return (high << 8) | low; +} + +// Right now, PWM output only works on the pins with +// hardware support. These are defined in the appropriate +// pins_*.c file. For the rest of the pins, we default +// to digital output. +void analogWrite(uint8_t pin, int val) +{ + // We need to make sure the PWM output is enabled for those pins + // that support it, as we turn it off when digitally reading or + // writing with them. Also, make sure the pin is in output mode + // for consistenty with Wiring, which doesn't require a pinMode + // call for the analog output pins. + pinMode(pin, OUTPUT); + if (val == 0) + { + digitalWrite(pin, LOW); + } + else if (val == 255) + { + digitalWrite(pin, HIGH); + } + else + { + switch(digitalPinToTimer(pin)) + { + // XXX fix needed for atmega8 + #if defined(TCCR0) && defined(COM00) && !defined(__AVR_ATmega8__) + case TIMER0A: + // connect pwm to pin on timer 0 + sbi(TCCR0, COM00); + OCR0 = val; // set pwm duty + break; + #endif + + #if defined(TCCR0A) && defined(COM0A1) + case TIMER0A: + // connect pwm to pin on timer 0, channel A + sbi(TCCR0A, COM0A1); + OCR0A = val; // set pwm duty + break; + #endif + + #if defined(TCCR0A) && defined(COM0B1) + case TIMER0B: + // connect pwm to pin on timer 0, channel B + sbi(TCCR0A, COM0B1); + OCR0B = val; // set pwm duty + break; + #endif + + #if defined(TCCR1A) && defined(COM1A1) + case TIMER1A: + // connect pwm to pin on timer 1, channel A + sbi(TCCR1A, COM1A1); + OCR1A = val; // set pwm duty + break; + #endif + + #if defined(TCCR1A) && defined(COM1B1) + case TIMER1B: + // connect pwm to pin on timer 1, channel B + sbi(TCCR1A, COM1B1); + OCR1B = val; // set pwm duty + break; + #endif + + #if defined(TCCR2) && defined(COM21) + case TIMER2: + // connect pwm to pin on timer 2 + sbi(TCCR2, COM21); + OCR2 = val; // set pwm duty + break; + #endif + + #if defined(TCCR2A) && defined(COM2A1) + case TIMER2A: + // connect pwm to pin on timer 2, channel A + sbi(TCCR2A, COM2A1); + OCR2A = val; // set pwm duty + break; + #endif + + #if defined(TCCR2A) && defined(COM2B1) + case TIMER2B: + // connect pwm to pin on timer 2, channel B + sbi(TCCR2A, COM2B1); + OCR2B = val; // set pwm duty + break; + #endif + + #if defined(TCCR3A) && defined(COM3A1) + case TIMER3A: + // connect pwm to pin on timer 3, channel A + sbi(TCCR3A, COM3A1); + OCR3A = val; // set pwm duty + break; + #endif + + #if defined(TCCR3A) && defined(COM3B1) + case TIMER3B: + // connect pwm to pin on timer 3, channel B + sbi(TCCR3A, COM3B1); + OCR3B = val; // set pwm duty + break; + #endif + + #if defined(TCCR3A) && defined(COM3C1) + case TIMER3C: + // connect pwm to pin on timer 3, channel C + sbi(TCCR3A, COM3C1); + OCR3C = val; // set pwm duty + break; + #endif + + #if defined(TCCR4A) + case TIMER4A: + //connect pwm to pin on timer 4, channel A + sbi(TCCR4A, COM4A1); + #if defined(COM4A0) // only used on 32U4 + cbi(TCCR4A, COM4A0); + #endif + OCR4A = val; // set pwm duty + break; + #endif + + #if defined(TCCR4A) && defined(COM4B1) + case TIMER4B: + // connect pwm to pin on timer 4, channel B + sbi(TCCR4A, COM4B1); + OCR4B = val; // set pwm duty + break; + #endif + + #if defined(TCCR4A) && defined(COM4C1) + case TIMER4C: + // connect pwm to pin on timer 4, channel C + sbi(TCCR4A, COM4C1); + OCR4C = val; // set pwm duty + break; + #endif + + #if defined(TCCR4C) && defined(COM4D1) + case TIMER4D: + // connect pwm to pin on timer 4, channel D + sbi(TCCR4C, COM4D1); + #if defined(COM4D0) // only used on 32U4 + cbi(TCCR4C, COM4D0); + #endif + OCR4D = val; // set pwm duty + break; + #endif + + + #if defined(TCCR5A) && defined(COM5A1) + case TIMER5A: + // connect pwm to pin on timer 5, channel A + sbi(TCCR5A, COM5A1); + OCR5A = val; // set pwm duty + break; + #endif + + #if defined(TCCR5A) && defined(COM5B1) + case TIMER5B: + // connect pwm to pin on timer 5, channel B + sbi(TCCR5A, COM5B1); + OCR5B = val; // set pwm duty + break; + #endif + + #if defined(TCCR5A) && defined(COM5C1) + case TIMER5C: + // connect pwm to pin on timer 5, channel C + sbi(TCCR5A, COM5C1); + OCR5C = val; // set pwm duty + break; + #endif + + case NOT_ON_TIMER: + default: + if (val < 128) { + digitalWrite(pin, LOW); + } else { + digitalWrite(pin, HIGH); + } + } + } +} +