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whitespace changes

This commit is contained in:
Michael Moon 2010-11-08 18:27:50 +11:00
parent a064ea8e37
commit 952ad4e2f3
1 changed files with 36 additions and 31 deletions
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67
analog.c
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@ -4,6 +4,7 @@
#ifndef ANALOG_MASK
#warning define ANALOG_MASK as a bitmask of all the analog channels you wish to use
#warning defining ANALOG_MASK as zero will prevent the analog subsystem from starting
#error ANALOG_MASK not defined
#endif
@ -40,26 +41,26 @@ volatile uint16_t adc_result[8] __attribute__ ((__section__ (".bss")));
void analog_init() {
#if ANALOG_MASK > 0
#ifdef PRR
PRR &= ~MASK(PRADC);
#elif defined PRR0
PRR0 &= ~MASK(PRADC);
#endif
ADMUX = REFERENCE;
// ADC frequency must be less than 200khz or we lose precision. At 16MHz system clock, we must use the full prescale value of 128 to get an ADC clock of 125khz.
ADCSRA = MASK(ADEN) | MASK(ADPS2) | MASK(ADPS1) | MASK(ADPS0);
#ifdef PRR
PRR &= ~MASK(PRADC);
#elif defined PRR0
PRR0 &= ~MASK(PRADC);
#endif
adc_counter = 0;
adc_running_mask = 1;
ADMUX = REFERENCE;
DDRC &= ANALOG_MASK;
DIDR0 = ANALOG_MASK & 0x3F;
// ADC frequency must be less than 200khz or we lose precision. At 16MHz system clock, we must use the full prescale value of 128 to get an ADC clock of 125khz.
ADCSRA = MASK(ADEN) | MASK(ADPS2) | MASK(ADPS1) | MASK(ADPS0);
// now we start the first conversion and leave the rest to the interrupt
ADCSRA |= MASK(ADIE) | MASK(ADSC);
#endif
adc_counter = 0;
adc_running_mask = 1;
DDRC &= ANALOG_MASK;
DIDR0 = ANALOG_MASK & 0x3F;
// now we start the first conversion and leave the rest to the interrupt
ADCSRA |= MASK(ADIE) | MASK(ADSC);
#endif /* ANALOG_MASK > 0 */
}
ISR(ADC_vect, ISR_NOBLOCK) {
@ -81,19 +82,23 @@ ISR(ADC_vect, ISR_NOBLOCK) {
}
uint16_t analog_read(uint8_t channel) {
uint16_t r;
#if ANALOG_MASK > 0
uint16_t r;
uint8_t sreg;
// save interrupt flag
sreg = SREG;
// disable interrupts
cli();
// atomic 16-bit copy
r = adc_result[channel];
// restore interrupt flag
SREG = sreg;
return r;
uint8_t sreg;
// save interrupt flag
sreg = SREG;
// disable interrupts
cli();
// atomic 16-bit copy
r = adc_result[channel];
// restore interrupt flag
SREG = sreg;
return r;
#else
return 0;
#endif
}