int analogRead(uint8_t pin)
{
#if defined( NUM_DIGITAL_PINS )
if ( pin >= NUM_DIGITAL_PINS ) pin -= NUM_DIGITAL_PINS; // allow for channel or pin numbers
#endif
// fix? Validate pin?
if(pin >= NUM_ANALOG_INPUTS) return 0; //Not a valid pin.
#ifndef ADCSRA
return digitalRead(analogInputToDigitalPin(pin)) ? 1023 : 0; //No ADC, so read as a digital pin instead.
#endif
#if defined(ADMUX)
ADMUX = ((analog_reference & ADMUX_REFS_MASK) << REFS0) | ((pin & ADMUX_MUX_MASK) << MUX0); //select the channel and reference
#if defined(REFS2)
ADMUX |= (((analog_reference & 0x04) >> 2) << REFS2); //some have an extra reference bit in a weird position.
#endif
#endif
#if defined(HAVE_ADC) && HAVE_ADC
sbi(ADCSRA, ADSC); //Start conversion
while(ADCSRA & (1<<ADSC)); //Wait for conversion to complete.
uint8_t low = ADCL;
uint8_t high = ADCH;
return (high << 8) | low;
#else
return LOW;
#endif
}
int16_t
Babuino::readAnalog(uint8_t i)
{
if (i < NUM_ANALOG_INPUTS) // defined in pins_arduino.h
return analogRead(analogInputToDigitalPin(i));
return -1;
}