48 lines
1.0 KiB
C++
Executable File
48 lines
1.0 KiB
C++
Executable File
#include <avr/sleep.h>
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#include <avr/wdt.h>
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const byte LED = 9;
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// watchdog interrupt
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ISR (WDT_vect)
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{
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wdt_disable(); // disable watchdog
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} // end of WDT_vect
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void setup () { }
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void loop ()
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{
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pinMode (LED, OUTPUT);
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digitalWrite (LED, HIGH);
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delay (50);
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digitalWrite (LED, LOW);
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pinMode (LED, INPUT);
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// disable ADC
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ADCSRA = 0;
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// clear various "reset" flags
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MCUSR = 0;
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// allow changes, disable reset
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WDTCSR = bit (WDCE) | bit (WDE);
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// set interrupt mode and an interval
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WDTCSR = bit (WDIE) | bit (WDP2) | bit (WDP1); // set WDIE, and 1 second delay
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wdt_reset(); // pat the dog
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set_sleep_mode (SLEEP_MODE_PWR_DOWN);
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noInterrupts (); // timed sequence follows
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sleep_enable();
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// turn off brown-out enable in software
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MCUCR = bit (BODS) | bit (BODSE);
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MCUCR = bit (BODS);
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interrupts (); // guarantees next instruction executed
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sleep_cpu ();
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// cancel sleep as a precaution
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sleep_disable();
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} // end of loop
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