28 lines
852 B
C
28 lines
852 B
C
/*
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Demo of the simplest on/off button code
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Button connected to PD2
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LEDs connected to PB0..PB7
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*/
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// ------- Preamble -------- //
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#include <avr/io.h>
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#include <util/delay.h>
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int main(void) {
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// -------- Inits --------- //
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PORTD |= (1 << PD2); /* initialize pullup resistor on our input pin */
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DDRB = 0xff; /* set up all LEDs for output */
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// ------ Event loop ------ //
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while (1) {
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if (bit_is_clear(PIND, PD2)) { /* look for button press */
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/* equivalent to if ((PIND & (1 << PD2)) == 0 ){ */
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PORTB = 0b00111100; /* pressed */
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}
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else { /* not pressed */
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PORTB = 0b11000011;
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}
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} /* End event loop */
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return 0;
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}
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