涂 桂旺 / HCSR04

test

Fork of HCSR04 by TVZ Mechatronics Team

HCSR04.h@4:aae70f15357f, 2015-12-07 (annotated)

Committer:
tbjazic
Date:
Mon Dec 07 09:37:21 2015 +0000
Revision:
4:aae70f15357f
Parent:
3:9a7899cf5e3a
Child:
5:a667b621f625
Functions for setting the sensor range and reading its values are added. Function for returning the measured distance in milimeters added.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
tbjazic 0:8871082486ac 1 #ifndef HCSR04_H_TVZMT
tbjazic 0:8871082486ac 2 #define HCSR04_H_TVZMT
tbjazic 0:8871082486ac 3
tbjazic 0:8871082486ac 4 /** A distance measurement class using ultrasonic sensor HC-SR04.
tbjazic 0:8871082486ac 5 *
tbjazic 0:8871082486ac 6 * Example of use:
tbjazic 2:aa59a9c531be 7 * @code
tbjazic 0:8871082486ac 8 * #include "mbed.h"
tbjazic 0:8871082486ac 9 * #include "HCSR04.h"
tbjazic 0:8871082486ac 10 *
tbjazic 0:8871082486ac 11 * Serial pc(USBTX, USBRX); // communication with terminal
tbjazic 0:8871082486ac 12 *
tbjazic 0:8871082486ac 13 * int main() {
tbjazic 0:8871082486ac 14 * HCSR04 sensor(p5, p7); // instantiate the sensor object
tbjazic 0:8871082486ac 15 * while(1) {
tbjazic 0:8871082486ac 16 * pc.printf("Distance: %5.1f cm\r", sensor.getDistance_cm());
tbjazic 0:8871082486ac 17 * wait_ms(975); // print the result every 1 second
tbjazic 0:8871082486ac 18 * }
tbjazic 0:8871082486ac 19 * }
tbjazic 2:aa59a9c531be 20 * @endcode
tbjazic 0:8871082486ac 21 */
tbjazic 0:8871082486ac 22 class HCSR04 {
tbjazic 0:8871082486ac 23
tbjazic 0:8871082486ac 24 public:
tbjazic 0:8871082486ac 25
tbjazic 0:8871082486ac 26 /** Receives two PinName variables.
tbjazic 0:8871082486ac 27 * @param echoPin mbed pin to which the echo signal is connected to
tbjazic 0:8871082486ac 28 * @param triggerPin mbed pin to which the trigger signal is connected to
tbjazic 0:8871082486ac 29 */
tbjazic 0:8871082486ac 30 HCSR04(PinName echoPin, PinName triggerPin);
tbjazic 0:8871082486ac 31
tbjazic 4:aae70f15357f 32 /** Calculates the distance in cm, with the calculation time of approximatelly 23.7 ms.
tbjazic 0:8871082486ac 33 * @returns distance of the measuring object in cm.
tbjazic 0:8871082486ac 34 */
tbjazic 0:8871082486ac 35 float getDistance_cm();
tbjazic 0:8871082486ac 36
tbjazic 4:aae70f15357f 37 /** Calculates the distance in mm, with the calculation time of approximatelly 23.7 ms.
tbjazic 4:aae70f15357f 38 * @returns distance of the measuring object in mm.
tbjazic 4:aae70f15357f 39 */
tbjazic 4:aae70f15357f 40 float getDistance_mm();
tbjazic 4:aae70f15357f 41
tbjazic 4:aae70f15357f 42 /** Sets the minimum and maximum ranges between the factory values of 2 cm and 400 cm.
tbjazic 4:aae70f15357f 43 * @param minRange Minimum range in cm. Must be between 2 cm and maxRange.
tbjazic 4:aae70f15357f 44 * @param maxRange Maximum range in cm. Must be between minRange and 400 cm.
tbjazic 4:aae70f15357f 45 */
tbjazic 4:aae70f15357f 46 void setRanges(float minRange, float maxRange);
tbjazic 4:aae70f15357f 47
tbjazic 4:aae70f15357f 48 /** Retreives the minimum sensor range set by the user.
tbjazic 4:aae70f15357f 49 * @returns the minimum sensor range set by the user in cm.
tbjazic 4:aae70f15357f 50 */
tbjazic 4:aae70f15357f 51 float getMinRange();
tbjazic 4:aae70f15357f 52
tbjazic 4:aae70f15357f 53 /** Retreives the maximum sensor range set by the user.
tbjazic 4:aae70f15357f 54 * @returns the maximum sensor range set by the user in cm.
tbjazic 4:aae70f15357f 55 */
tbjazic 4:aae70f15357f 56 float getMaxRange();
tbjazic 4:aae70f15357f 57
tbjazic 0:8871082486ac 58 private:
tbjazic 0:8871082486ac 59
tbjazic 0:8871082486ac 60 InterruptIn echo; // echo pin
tbjazic 0:8871082486ac 61 DigitalOut trigger; // trigger pin
tbjazic 0:8871082486ac 62 Timer timer; // echo pulsewidth measurement
tbjazic 0:8871082486ac 63 float distance; // store the distance in cm
tbjazic 3:9a7899cf5e3a 64 float minDistance; // minimum measurable distance
tbjazic 3:9a7899cf5e3a 65 float maxDistance; // maximum measurable distance
tbjazic 0:8871082486ac 66
tbjazic 0:8871082486ac 67 /** Start the timer. */
tbjazic 0:8871082486ac 68 void startTimer();
tbjazic 0:8871082486ac 69
tbjazic 0:8871082486ac 70 /** Stop the timer. */
tbjazic 0:8871082486ac 71 void stopTimer();
tbjazic 0:8871082486ac 72
tbjazic 0:8871082486ac 73 /** Initialization. */
tbjazic 0:8871082486ac 74 void init();
tbjazic 0:8871082486ac 75
tbjazic 0:8871082486ac 76 /** Start the measurement. */
tbjazic 0:8871082486ac 77 void startMeasurement();
tbjazic 0:8871082486ac 78 };
tbjazic 0:8871082486ac 79
tbjazic 0:8871082486ac 80 #endif