32 lines
779 B
C
32 lines
779 B
C
#ifndef SONAR_H
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#define SONAR_H
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#include "common.h"
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// Trigger
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#define TRIG_DDR DDRC
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#define TRIG_PORT PORTC
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#define TRIG_PIN PINC
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#define TRIG_BIT PC4
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// Echo
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#define ECHO_DDR DDRC
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#define ECHO_PORT PORTC
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#define ECHO_PIN PINC
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#define ECHO_BIT PC5
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#define SPEED_OF_SOUND 343 // 20°C dry air (m/s)
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#define MAX_SONAR_RANGE 8 // Trigger + echo (m)
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#define MIN_SONAR_RANGE 4 // Minimum distance that is still reliable
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#define SONAR_DELAY 60 // Timeout for return signal
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#define TIMER_MAX 255 // For 8-bit timer
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#define CYCLES_PER_US (F_CPU / 1000000)
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#define SONAR_TIMEOUT (F_CPU * MAX_SONAR_RANGE) / SPEED_OF_SOUND
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#define ECHO_TIMEOUT -1
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void init_sonar(void);
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int32_t read_sonar(void);
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#endif /* SONAR_H */
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