Motion Sensor project code help

[Hemant]

`const int TriggerPin = 8; //Trig pin
const int EchoPin = 9; //Echo pin
long Duration = 0;
long Distance_mm = Distance(Duration); 
void setup(){
pinMode(TriggerPin,OUTPUT); // Trigger is an output pin
pinMode(EchoPin,INPUT); // Echo is an input pin
Serial.begin(9600); // Open a connection to the Serial monitor
pinMode(13, OUTPUT);
}

void loop(){
digitalWrite(TriggerPin, LOW);
delayMicroseconds(2);
digitalWrite(TriggerPin, HIGH); // Trigger pin to HIGH
delayMicroseconds(10); // 10us high
digitalWrite(TriggerPin, LOW); // Trigger pin to HIGH

Duration = pulseIn(EchoPin,HIGH); // Waits for the echo pin to get high
// returns the Duration in microseconds
 // Use function to calculate the distance

Serial.print("Distance = "); // Output to serial
Serial.print(Distance_mm);
Serial.println(" mm");

delay(1000); // Wait to do next measurement
}
if(long Distance<100){
digitalWrite(13, HIGH);
}
else{
digitalWrite(13, LOW);
 long Distance(long time)
}
{
// Calculates the Distance in mm
// ((time)*(Speed of sound))/ toward and backward of object) * 10

long DistanceCalc; // Calculation variable
DistanceCalc = ((time*0.343) / 2); // Actual calculation in mm
//DistanceCalc = time / 74 / 2; // Actual calculation in inches
return DistanceCalc; // return calculated value
}`

Hi guys, I'm new to coding, and I keep getting error messages which I can't understand, (I also can't really understand some of this code), I'm hoping for some guidance on how to resolve the errors. I'm trying to make it so that when the sensor detects something less than a 100mm to it, it turns the LED on.

as well as expected unqualified-id before '{' token
Please help me... and thank you

[Ron_Blain]

Hi and welcome to the forums.

You mention motion sensor but with a trigger and waiting for a return it looks like you have a distance sensor, maybe similar to this type.

What would help is a wiring diagram that goes with your code and where sis the code come from?

You may want to give this a read. It is written around the sensor type I linked to.

Ron

[Railroader]

@Hemant

long Distance_mm = Distance(Duration);

What would "Distance()" be?
There is no definition of the "Distance function".

[xfpd]

// These lines are good

const int TriggerPin = 8; //Trig pin
const int EchoPin = 9; //Echo pin
long Duration = 0;
long Distance_mm;

// Remove this line. It should not be in this area.
// It is calling a function and expecting a return value.
// I have commented the line out.

// long Distance_mm = Distance(Duration);

// These lines are good.

void setup() {
  pinMode(TriggerPin, OUTPUT); // Trigger is an output pin
  pinMode(EchoPin, INPUT); // Echo is an input pin
  Serial.begin(9600); // Open a connection to the Serial monitor

// Let the reader know this is an LED in the comment field

  pinMode(13, OUTPUT); // LED_BUILTIN
}

// These lines are good.

void loop() {
  digitalWrite(TriggerPin, LOW);
  delayMicroseconds(2);
  digitalWrite(TriggerPin, HIGH); // Trigger pin to HIGH
  delayMicroseconds(10); // 10us high
  digitalWrite(TriggerPin, LOW); // Trigger pin to HIGH

  Duration = pulseIn(EchoPin, HIGH); // Waits for the echo pin to get high  returns the Duration in microseconds

// At this point your copy/paste went wrong.
// You pasted the external function "Distance" into the loop() function. 
// This is how the distance function should have been called

  // Use function to calculate the distance
  Distance_mm = Distance(Duration);

  // Calculates the Distance in mm
  // ((time)*(Speed of sound))/ toward and backward of object) * 10

  if (Distance < 100) {
    digitalWrite(13, HIGH); // turn LED on
  }
  else {
    digitalWrite(13, LOW); // turn LED off
  }

  Serial.print("Distance = "); // Output to serial
  Serial.print(Distance_mm);
  Serial.println(" mm");

  delay(1000); // Wait to do next measurement
}

// This function was pasted into the loop() function... 
// Moved here to be used as an external function
// This function will receive a 'long' and call it 'time' ...
// ... and return a 'long' locally called 'DistanceCalc'

long Distance(long time) {
   // Calculation variable
  long DistanceCalc = ((time * 0.343) / 2); // Actual calculation in mm
  //DistanceCalc = time / 74 / 2; // Actual calculation in inches
  return DistanceCalc; // return calculated value
}

[Hemant]

ty man

[Hemant]

just wondering, what does an external function symbolize?

I really appreciate y'all help, my hopes weren't really high and I couldn't find any tutorials on this,

Tysm guys

[xfpd]

@Hemant

external function

External functions (or just "functions") allow you to write a main program and "call" external functions. For example:

void setup()  {
  Serial.begin(9600);
}
void loop() {
  Serial.println("Hello, World!");
  delay(500);
}

You are stuck with printing, Hello, World!... but what if you wanted something different?

In the original program, the calculation was moved "externally" so you could make changes to the "external function" without disturbing the original program... so this example might look like this...

int count; // global variable

void setup() {
  Serial.begin(9600);
}

void loop() {
  Serial.print("Hello, ");
  extfun(); // this calling an external function
  delay(500); // slow the output down
}

void extfun() { // this is the function being call from inside 'loop()'
  Serial.println("World of Warcraft!");
}