Library for distance measurement with device HC-SR04 and similar. More...

Data Structures
class	Distance_HC_SR04
	Distance_HC_SR04 class. More...
Enumerations
enum	Distance_HC_SR04_state { IDLE, STARTED, COMPLETED, TIMEOUT, OUT_OF_RANGE_MIN, OUT_OF_RANGE_MAX, ERROR_SIG }
	Definition of measurement FSM states. More...

Detailed Description

Library for distance measurement with device HC-SR04 and similar.

Date:: 21. Dec 2015 Synchronous and asynchronous library for ultrasonic distance measurement for the device HC-SR04 with error handling functionality (out of range detection, HW error detection). Main features: "echo" puls duration measurement, distance measurement from "echo" pulse duration, detection of "echo" signal malfunction, timeout detection, detection of measured values outside reliable limits (min, max)

Definition in file Distance_HC_SR04.h.

Enumeration Type Documentation

Definition of measurement FSM states.

Measurement FSM (Finite State Machine) states definition.

Enumerator:

IDLE	No activity. Ready to start measurement with trigger(). This is state after reset().
STARTED	Measurement started and in progress. This is state after trigger().
COMPLETED	Measurement succesfuly completed by falling edge of echo signal. Measured values in range.
TIMEOUT	It was not possible to complete echo pulse width measurement in given time. Measurement cancelled.
OUT_OF_RANGE_MIN	Measurement completed. Measured distance under reliable range.
OUT_OF_RANGE_MAX	Measurement completed. Measured distance over reliable range.
ERROR_SIG	Faulty value of echo signal just after trigger pulse (echo != 0). Possible HW fault.

Definition at line 28 of file Distance_HC_SR04.h.