Cayenne / HCSR04 / NODEMCU

shramik_salgaonkar · April 19, 2018, 8:54am

this is because most of your distance value is greater than 95 cm.
so when we do this

  y = map(distance, 95, 10, 0, 100);
  y = constrain(y, 0, 100);

all values in the range of 95 to 10 are taken and rest are ignored.

terreemer · April 19, 2018, 8:59am

I agree but why my sensors that are the same distance from the wall do not return me the same distance while the code is the same.

Distance: 36
[345044] Publish: topic 1, channel 10, value 69, subkey , key
[345045] Publish: topic 1, channel 11, value 69, subkey null, key t1
[345051] Publish: topic 1, channel 12, value 69, subkey null, key analog_sensor
Distance2: 0
[351135] Publish: topic 1, channel 20, value 105, subkey , key
[351137] Publish: topic 1, channel 21, value 100, subkey null, key t1
[351145] Publish: topic 1, channel 22, value 100, subkey null, key analog_sensor
[352233] Connection ok
Distance: 35
[357236] Publish: topic 1, channel 10, value 70, subkey , key
[357238] Publish: topic 1, channel 11, value 70, subkey null, key t1
[357244] Publish: topic 1, channel 12, value 70, subkey null, key analog_sensor
Distance2: 0
[363328] Publish: topic 1, channel 20, value 105, subkey , key
[363329] Publish: topic 1, channel 21, value 100, subkey null, key t1
[363337] Publish: topic 1, channel 22, value 100, subkey null, key analog_sensor
[364427] Connection ok
Distance: 35
[369431] Publish: topic 1, channel 10, value 70, subkey , key
[369432] Publish: topic 1, channel 11, value 70, subkey null, key t1
[369438] Publish: topic 1, channel 12, value 70, subkey null, key analog_sensor
Distance2: 0

terreemer · April 19, 2018, 9:02am

Other exemple :

Distance2: 2
[521273] Publish: topic 1, channel 20, value 103, subkey , key
[521274] Publish: topic 1, channel 21, value 100, subkey null, key t1
[521282] Publish: topic 1, channel 22, value 100, subkey null, key analog_sensor
[522373] Connection ok
Distance: 40
[527377] Publish: topic 1, channel 10, value 65, subkey , key
[527379] Publish: topic 1, channel 11, value 64, subkey null, key t1
[527384] Publish: topic 1, channel 12, value 64, subkey null, key analog_sensor
Distance2: 2
[532483] Publish: topic 1, channel 20, value 103, subkey , key
[532484] Publish: topic 1, channel 21, value 100, subkey null, key t1
[532492] Publish: topic 1, channel 22, value 100, subkey null, key analog_sensor
[533583] Connection ok
Distance: 40
[538586] Publish: topic 1, channel 10, value 65, subkey , key
[538588] Publish: topic 1, channel 11, value 64, subkey null, key t1
[538594] Publish: topic 1, channel 12, value 64, subkey null, key analog_sensor
Distance2: 2

SuperNinja · April 19, 2018, 9:05am

Have you inverted sensor ? Perhaps a defect unit ?

shramik_salgaonkar · April 19, 2018, 9:07am

might be. give it a try. or remove all cayenne code and test only two sensor code.

terreemer · April 19, 2018, 9:58am

So, without the cayenne code everything is OK

Distance2: 45
Distance: 45
Distance2: 44
Distance: 44
Distance2: 44
Distance: 44
Distance2: 167
Distance: 167
Distance2: 167
Distance: 167
Distance2: 167

terreemer · April 19, 2018, 10:36am

n precision, if I comment on the Cayenne.virtualWrite lines for both sensors the measurements are good in the monitor.

void loop() {
Cayenne.loop();

//HCSR04 N°1

// Clears the trigPin
digitalWrite(trigPin, LOW);
delayMicroseconds(2);

// Sets the trigPin on HIGH state for 10 micro seconds
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);

// Reads the echoPin, returns the sound wave travel time in microseconds
duration = pulseIn(echoPin, HIGH);

// Calculating the distance
distance = duration * 0.034 / 2;
// Prints the distance on the Serial Monitor
Serial.print("Distance: ");
Serial.println(distance);
y = map(distance, 95, 10, 0, 100);
y = constrain(y, 0, 100);
delay(5000);
if (millis() - lastMillis > 10000) {
lastMillis = millis();
//Cayenne.virtualWrite(10, 105-distance);
//Cayenne.virtualWrite(11, y, “t1”, “null”);
//Cayenne.virtualWrite(12, y, “analog_sensor”, “null”);

//HCSR04 N°2

// Clears the trigPin N°2
digitalWrite(trigPin2, LOW);
delayMicroseconds(2);

// Sets the trigPin N°2 on HIGH state for 10 micro seconds
digitalWrite(trigPin2, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin2, LOW);

// Reads the echoPin N°2, returns the sound wave travel time in microseconds
duration2 = pulseIn(echoPin2, HIGH);

// Calculating the distance N°2
distance2 = duration2 * 0.034 / 2;
// Prints the distance N°2 on the Serial Monitor
Serial.print("Distance2: ");
Serial.println(distance2);
y2 = map(distance2, 95, 10, 0, 100);
y2 = constrain(y2, 0, 100);
delay(5000);
if (millis() - lastMillis2 > 10000) {
lastMillis2 = millis();
//Cayenne.virtualWrite(20, 105-distance2);
//Cayenne.virtualWrite(21, y2, “t1”, “null”);
//Cayenne.virtualWrite(22, y2, “analog_sensor”, “null”);

}
}
}

terreemer · April 19, 2018, 10:58am

last test done:
if i comment only the 3 lines cayenne.virtualwrite of the first sensor it works and conversely if i comment only the 3 lines cayenne.virtualwrite the second sensor it works too.

It’s OK :
void loop() {
Cayenne.loop();

//HCSR04 N°1

// Clears the trigPin
digitalWrite(trigPin, LOW);
delayMicroseconds(2);

// Sets the trigPin on HIGH state for 10 micro seconds
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);

// Reads the echoPin, returns the sound wave travel time in microseconds
duration = pulseIn(echoPin, HIGH);

// Calculating the distance
distance = duration * 0.034 / 2;
// Prints the distance on the Serial Monitor
Serial.print("Distance: ");
Serial.println(distance);
y = map(distance, 95, 10, 0, 100);
y = constrain(y, 0, 100);
delay(5000);
if (millis() - lastMillis > 10000) {
lastMillis = millis();
//Cayenne.virtualWrite(10, 105-distance);
//Cayenne.virtualWrite(11, y, “t1”, “null”);
//Cayenne.virtualWrite(12, y, “analog_sensor”, “null”);

//HCSR04 N°2

// Clears the trigPin N°2
digitalWrite(trigPin2, LOW);
delayMicroseconds(2);

// Sets the trigPin N°2 on HIGH state for 10 micro seconds
digitalWrite(trigPin2, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin2, LOW);

// Reads the echoPin N°2, returns the sound wave travel time in microseconds
duration2 = pulseIn(echoPin2, HIGH);

// Calculating the distance N°2
distance2 = duration2 * 0.034 / 2;
// Prints the distance N°2 on the Serial Monitor
Serial.print("Distance2: ");
Serial.println(distance2);
y2 = map(distance2, 95, 10, 0, 100);
y2 = constrain(y2, 0, 100);
delay(5000);
if (millis() - lastMillis2 > 10000) {
lastMillis2 = millis();
Cayenne.virtualWrite(20, 105-distance2);
Cayenne.virtualWrite(21, y2, “t1”, “null”);
Cayenne.virtualWrite(22, y2, “analog_sensor”, “null”);

}
}
}

it’sOk

void loop() {
Cayenne.loop();

//HCSR04 N°1

// Clears the trigPin
digitalWrite(trigPin, LOW);
delayMicroseconds(2);

// Sets the trigPin on HIGH state for 10 micro seconds
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);

// Reads the echoPin, returns the sound wave travel time in microseconds
duration = pulseIn(echoPin, HIGH);

// Calculating the distance
distance = duration * 0.034 / 2;
// Prints the distance on the Serial Monitor
Serial.print("Distance: ");
Serial.println(distance);
y = map(distance, 95, 10, 0, 100);
y = constrain(y, 0, 100);
delay(5000);
if (millis() - lastMillis > 10000) {
lastMillis = millis();
Cayenne.virtualWrite(10, 105-distance);
Cayenne.virtualWrite(11, y, “t1”, “null”);
Cayenne.virtualWrite(12, y, “analog_sensor”, “null”);

//HCSR04 N°2

// Clears the trigPin N°2
digitalWrite(trigPin2, LOW);
delayMicroseconds(2);

// Sets the trigPin N°2 on HIGH state for 10 micro seconds
digitalWrite(trigPin2, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin2, LOW);

// Reads the echoPin N°2, returns the sound wave travel time in microseconds
duration2 = pulseIn(echoPin2, HIGH);

// Calculating the distance N°2
distance2 = duration2 * 0.034 / 2;
// Prints the distance N°2 on the Serial Monitor
Serial.print("Distance2: ");
Serial.println(distance2);
y2 = map(distance2, 95, 10, 0, 100);
y2 = constrain(y2, 0, 100);
delay(5000);
if (millis() - lastMillis2 > 10000) {
lastMillis2 = millis();
//Cayenne.virtualWrite(20, 105-distance2);
//Cayenne.virtualWrite(21, y2, “t1”, “null”);
//Cayenne.virtualWrite(22, y2, “analog_sensor”, “null”);

}
}
}

terreemer · April 19, 2018, 1:13pm

I just redo all my cabling and the code is OK now.

Thank you so much for the time spent helping me

shramik_salgaonkar · April 19, 2018, 1:28pm

you can also use NewPing library for ultrasonic sensors. much better and easier to add multiple sensors.

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