All About Max Sonar EZ0 and Arduino

I Searched In the Internet about EZ0 Ultrasonic And I found Many information in the datasheet for this sensor , I will show you how we can program this sensor in Arduino IDE .

At first , the Datasheet " You can see it Here " Have all Specification and Features For this sensor .

The EZ0 Sonar detects objects from 0-inches to 254-inches (6.45-meters) and provides sonar range information from 6-inches out to 254-inches with 1-inch resolution. Objects from 0-inches to 6-inches typically range as 6- inches

This sensor Has 3 Output formats To interface with :

1 ) Analog interface .

2) Pulse width Modulation "PW".

3) Serial Interface .

Material :

1) Arduino Board " I used Arduino Nano".

2) Ultrasonic Max Sonar EZ0 .

3)Wires and BreadBoard .


Download the library for this sensor from HERE

The Analog Interface is the easiest way to communicate with this sensor , there is a directly proportional between Distance and Output voltage .

Outputs analog voltage with a scaling factor of (Vcc/512) per inch .

For example , a voltage supply of 5V yields ~9.8mV/inch , a voltage supply of 3.3 V yields ~6.4mV/inch.

The analog Output voltage not accurate rather than PW And serial . so I prefer to use PW or serial .

this is a simple code :

// Written by : Mohannad Rawashdeh
// this code foe EZ0 Max sonar , analog interface
// https://www.instructables.com/member/Mohannad+Rawashdeh/
//.................................................
float Inch=0.00;
float cm=0.00;
int SonarPin=A0;
int sensorValue;
void setup(){
pinMode(SonarPin,INPUT);
Serial.begin(9600);
}
void loop(){
sensorValue=analogRead(SonarPin);
delay(50);
Inch= (sensorValue*0.497);
cm=Inch*2.54;
Serial.println(sensorValue);
Serial.print(Inch);
Serial.println("inch");
Serial.print(cm);
Serial.println("cm");
delay(100);
}

Pulse width "PW" Is another way to communicate with this sensor .

This pin outputs a pulse width representation of range. The distance can be calculated using the scale factor of 147uS per inch.

So using Pulse in to calculate the distance .

I prepared This Library for this method , You can Download from attachment .

This code without Library and with Median/Mode filter :
//...........................................................
// this code Based on : http://playground.arduino.cc/Main/MaxSonar
int pw_pin=7;
int arraysize = 9;
int array[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0};
long inch;
int exact_cm_value;
void setup() {
// put your setup code here, to run once:
pinMode(pw_pin, INPUT);
Serial.begin(9600);
}
void sensorRead(){
for(int i = 0; i < arraysize; i++)
{
inch = pulseIn(pw_pin, HIGH);
array[i] = inch/58;
delay(10);
}
}
void array_arrangment(int *a,int n){
// Author: Bill Gentles, Nov. 12, 2010)
for (int i = 1; i < n; ++i)
{
int j = a[i];
int k;
for (k = i - 1; (k >= 0) && (j < a[k]); k--)
{
a[k + 1] = a[k];
}
a[k + 1] = j;
}
}

int filter(int *a,int n){
int i = 0;
int count = 0;
int maxCount = 0;
int filter = 0;
int median;
int prevCount = 0;
while(i<(n-1)){
prevCount=count;
count=0;
while(a[i]==a[i+1]){
count++;
i++;
}
if(count>prevCount && count>maxCount){
filter=a[i];
maxCount=count;
median=0;
}
if(count==0){
i++;
}
if(count==maxCount){//If the dataset has 2 or more modes.
median=1;
}
if(filter==0||median==1){//Return the median if there is no mode.
filter=a[(n/2)];
}

return filter;

}
}
void loop() {
// put your main code here, to run repeatedly:
sensorRead();
array_arrangment(array,arraysize);
exact_cm_value= filter(array,arraysize);
Serial.print("The distance = ");
Serial.print(exact_cm_value);
Serial.println(" cm ");
delay(100);

}

Library code :
//......................................................
#include "SonarEZ0pw.h"
SonarEZ0pw Sonar(7); // pin D7
float cm_dis=0.00;
float Inch_dis=0.00;
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
}

void loop() {
// put your main code here, to run repeatedly:
cm_dis= Sonar.Distance(cm); // To calculate the distance in cm
Inch_dis=Sonar.Distance(inch);// To calculate the distance in Inch
Serial.println("Distance " );
Serial.print(Inch_dis);
Serial.println(" inch ");
Serial.print(cm_dis);
Serial.println(" cm ");
delay(250);
}