Honza T.
Development and testing of ultrasonic distance measurement library for device HC-SR04.
Dependencies: TextLCD_improved mbed Distance_HC_SR04
Diff: main.cpp
- Branch:
- CLASS_IMPLEMENTATION
- Revision:
- 4:bb5819be6ac3
- Parent:
- 3:cb5931861f4e
- Child:
- 5:1a69f40177b0
--- a/main.cpp Sun Dec 20 21:37:27 2015 +0000
+++ b/main.cpp Sun Dec 20 22:29:18 2015 +0000
@@ -1,12 +1,12 @@
/*
- * TSK_MAIN.CPP
+ * MAIN.CPP
*/
#include "mbed.h"
#include "TextLCD.h"
#define TIMEOUT_DELAY_US (25000)
-#define CALC_COEFF (1000.0f*340.0f/2)
+#define CALC_COEFF (340.0f/(2.0f*1000.0f))
#define TICKS_RANGE_MAX (15000)
#define TICKS_RANGE_MIN (150)
#define TRIG_PULSE_US (50)
@@ -17,28 +17,9 @@
TextLCD lcd(PA_8, PA_7, PA_9, PA_1, PB_5, PA_10, TextLCD::LCD16x2);
-static DigitalOut trigDist(PB_9);
-static DigitalIn echoDist(PA_6);
-
-static uint32_t timer_ticks;
-static float time_float;
-static uint32_t timer_ticks_min;
-
-static Timer timer;
-
-static Timeout timeout;
-
-static volatile Distance_HC_SR04_state state;
-
-void tout(void) {
- if (state == STARTED)
- state = TIMEOUT;
-}
-
-
class Distance_HC_SR04 {
public:
- Distance_HC_SR04(PinName trig, PinName echo, uint32_t tout_us = TIMEOUT_DELAY_US, float coeff = CALC_COEFF) : _trig(trig), _echo(echo), _tout_us(tout_us), _coeff(coeff) {
+ Distance_HC_SR04(PinName trig, PinName echo, uint32_t tout_us = TIMEOUT_DELAY_US, float coeff = CALC_COEFF, uint32_t tmin_us = TICKS_RANGE_MIN, uint32_t tmax_us = TICKS_RANGE_MAX) : _trig(trig), _echo(echo), _tout_us(tout_us), _coeff(coeff), _tmin_us(tmin_us), _tmax_us(tmax_us) {
_trig = 0;
_state = IDLE;
}
@@ -57,7 +38,7 @@
if (_echo == 0) {
_state = STARTED;
- timeout.attach_us(this, &Distance_HC_SR04::_tout, TIMEOUT_DELAY_US);
+ _timeout.attach_us(this, &Distance_HC_SR04::_tout, TIMEOUT_DELAY_US);
_echo.rise(this, &Distance_HC_SR04::_rising);
_echo.fall(this, &Distance_HC_SR04::_falling);
@@ -92,7 +73,7 @@
}
float getDistance(void) {
- return _ticks_us/_coeff;
+ return _ticks_us*_coeff;
}
float getCoeff(void) {
@@ -104,7 +85,7 @@
}
float measureDistance(void) {
- return measureTicks()/_coeff;
+ return measureTicks()*_coeff;
}
uint32_t measureTicks(void) {
@@ -146,7 +127,16 @@
if (_state == STARTED) {
_timer.stop();
_ticks_us = _timer.read_us();
- state = COMPLETED;
+
+ if (_ticks_us < _tmin_us) {
+ _ticks_us = 0;
+ _state = OUT_OF_RANGE_MIN;
+ } else if (_ticks_us > _tmax_us) {
+ _ticks_us = 0;
+ _state = OUT_OF_RANGE_MAX;
+ } else {
+ _state = COMPLETED;
+ }
}
}
@@ -154,22 +144,20 @@
DigitalOut _trig;
InterruptIn _echo;
uint32_t _tout_us;
+ uint32_t _tmin_us;
+ uint32_t _tmax_us;
float _coeff;
Timer _timer;
Timeout _timeout;
volatile Distance_HC_SR04_state _state;
- uint32_t _ticks_us;
+ uint32_t _ticks_us;
};
int main() {
-
- trigDist = 0;
- state = IDLE;
- timer_ticks_min = 999999;
wait_ms(250);
lcd.cls();
@@ -179,119 +167,60 @@
lcd.locate(0, 1);
lcd.printf("Row 2");
- while (true) {
- // Priprava
- state = STARTED;
- timeout.attach_us(&tout, TIMEOUT_DELAY_US);
+ Distance_HC_SR04 distFront(PB_9, PA_6);
+ uint32_t ticks_us;
+ float distance;
- // Dej puls na trig
- trigDist = 1;
- wait_us(500);
- trigDist = 0;
-
- // Zkontroluj signal
- if (echoDist != 0) {
- state = ERROR_SIG;
- timer_ticks = 0;
- lcd.cls();
- lcd.printf("Dist.: ---", timer_ticks);
- lcd.locate(0, 1);
- lcd.printf("ERROR_SIG");
- } else {
- // Vynuluj timer
- timer.stop();
- timer.reset();
-
- // Cekej na hrany na Echo
- while (echoDist == 0 && state == STARTED)
- ;
-
- timer.start();
-
- while (echoDist == 1 && state == STARTED)
- ;
-
- if (state == STARTED) {
- state = COMPLETED;
- timer.stop();
+ while (true) {
+ ticks_us = distFront.measureTicks();
+ distance = distFront.getDistance();
+
+ lcd.cls();
- timer_ticks = timer.read_us();
- time_float = timer.read()*CALC_COEFF;
-
- timer_ticks_min = (timer_ticks_min < timer_ticks) ? timer_ticks_min : timer_ticks;
+ switch (distFront.getState()) {
+ case COMPLETED:
+ lcd.printf("Dist.: %u", ticks_us);
+ lcd.locate(0, 1);
+ lcd.printf("Dist.: %.3f", distance);
- if (timer_ticks < TICKS_RANGE_MIN) {
- timer_ticks = 0;
- time_float = 0.0f;
-
- state = OUT_OF_RANGE_MIN;
-
- lcd.cls();
- lcd.printf("Dist.: ---");
- lcd.locate(0, 1);
- lcd.printf("OUT_OF_RANGE_MIN");
- } else if (timer_ticks > TICKS_RANGE_MAX) {
- timer_ticks = 0;
- time_float = 0.0f;
-
- state = OUT_OF_RANGE_MAX;
-
- lcd.cls();
- lcd.printf("Dist.: ---");
- lcd.locate(0, 1);
- lcd.printf("OUT_OF_RANGE_MAX");
- } else {
- lcd.cls();
- lcd.printf("Dist.: %u %u", timer_ticks, timer_ticks_min);
- lcd.locate(0, 1);
- lcd.printf("Dist.: %.3f", time_float);
- }
- } else {
- timer.stop();
- timer_ticks = 0;
- time_float = 0.0f;
-
- lcd.cls();
- lcd.printf("Dist.: ---", timer_ticks);
+ break;
+
+ case TIMEOUT:
+ lcd.printf("Dist.: ---");
lcd.locate(0, 1);
lcd.printf("TIMEOUT");
- }
+
+ break;
+
+ case ERROR_SIG:
+ lcd.printf("Dist.: ---");
+ lcd.locate(0, 1);
+ lcd.printf("ERROR_SIG");
+
+ break;
+
+ case OUT_OF_RANGE_MIN:
+ lcd.printf("Dist.: ---");
+ lcd.locate(0, 1);
+ lcd.printf("OUT_OF_RANGE_MIN");
+
+ break;
+
+ case OUT_OF_RANGE_MAX:
+ lcd.printf("Dist.: ---");
+ lcd.locate(0, 1);
+ lcd.printf("OUT_OF_RANGE_MAX");
+
+ break;
+
+ default:
+ lcd.printf("Dist.: ---");
+ lcd.locate(0, 1);
+ lcd.printf("OTHER");
+
+ break;
}
- timeout.detach();
wait_ms(100);
-
- state = IDLE;
}
}
-
-
-/*
-// A class for flip()-ing a DigitalOut
-class Flipper {
-public:
- Flipper(PinName pin) : _pin(pin) {
- _pin = 0;
- }
- void flip() {
- _pin = !_pin;
- }
-private:
- DigitalOut _pin;
-};
-
-DigitalOut led1(LED1);
-Flipper f(LED2);
-Timeout t;
-
-int main() {
- t.attach(&f, &Flipper::flip, 2.0); // the address of the object, member function, and interval
-
- // spin in a main loop. flipper will interrupt it to call flip
- while(1) {
- led1 = !led1;
- wait(0.2);
- }
-}
-
- */
\ No newline at end of file