Hi I have this error and am puzzled trying to fix it.
/*************************************************************
Download latest Blynk library here:
https://github.com/blynkkk/blynk-library/releases/latest
Blynk is a platform with iOS and Android apps to control
Arduino, Raspberry Pi and the likes over the Internet.
You can easily build graphic interfaces for all your
projects by simply dragging and dropping widgets.
Downloads, docs, tutorials: http://www.blynk.cc
Sketch generator: http://examples.blynk.cc
Blynk community: http://community.blynk.cc
Follow us: http://www.fb.com/blynkapp
http://twitter.com/blynk_app
Blynk library is licensed under MIT license
This example code is in public domain.
*************************************************************
You’ll need:
- Blynk App (download from AppStore or Google Play)
- ESP32 board
- Decide how to connect to Blynk
(USB, Ethernet, Wi-Fi, Bluetooth, ...)
There is a bunch of great example sketches included to show you how to get
started. Think of them as LEGO bricks and combine them as you wish.
For example, take the Ethernet Shield sketch and combine it with the
Servo example, or choose a USB sketch and add a code from SendData
example.
*************************************************************/
/* Comment this out to disable prints and save space */
#define BLYNK_PRINT Serial
#define USE_AVG
#include <WiFi.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp32.h>
// Arduino pin numbers.
const int sharpLEDPin = 18; // Arduino digital pin 7 connect to sensor LED.
const int sharpVoPin = 25; // Arduino analog pin 5 connect to sensor Vo.
// For averaging last N raw voltage readings.
#ifdef USE_AVG
#define N 100
static unsigned long VoRawTotal = 0;
static int VoRawCount = 0;
#endif // USE_AVG
// Set the typical output voltage in Volts when there is zero dust.
static float Voc = 0.6;
// Use the typical sensitivity in units of V per 100ug/m3.
const float K = 0.5;
/////////////////////////////////////////////////////////////////////////////
// Helper functions to print a data value to the serial monitor.
void printValue(String text, unsigned int value, bool isLast = false) {
Serial.print(text);
Serial.print("=");
Serial.print(value);
if (!isLast) {
Serial.print(", ");
}
}
void printFValue(String text, float value, String units, bool isLast = false) {
Serial.print(text);
Serial.print("=");
Serial.print(value);
Serial.print(units);
if (!isLast) {
Serial.print(", ");
}
}
// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth[] = "R2UBBwrl0XoYUjcPWH5gWqlib3eMIJwl";
// Your WiFi credentials.
// Set password to "" for open networks.
char ssid[] = "YourNetworkName";
char pass[] = "YourPassword";
void setup()
{
// Debug console
Serial.begin(9600);
Blynk.begin(auth, ssid, pass);
// You can also specify server:
//Blynk.begin(auth, ssid, pass, "blynk-cloud.com", 80);
//Blynk.begin(auth, ssid, pass, IPAddress(192,168,1,100), 8080);
}
// Set LED pin for output.
pinMode(sharpLEDPin, OUTPUT);
// Start the hardware serial port for the serial monitor.
Serial.begin(9600);
// Wait two seconds for startup.
Serial.println("");
Serial.println("GP2Y1014AU0F Demo");
Serial.println("=================");
void loop()
{
Blynk.run();
// You can inject your own code or combine it with other sketches.
// Check other examples on how to communicate with Blynk. Remember
// to avoid delay() function!
// Turn on the dust sensor LED by setting digital pin LOW.
digitalWrite(sharpLEDPin, LOW);
// Wait 0.28ms before taking a reading of the output voltage as per spec.
delayMicroseconds(280);
// Record the output voltage. This operation takes around 100 microseconds.
int VoRaw = analogRead(sharpVoPin);
// Turn the dust sensor LED off by setting digital pin HIGH.
digitalWrite(sharpLEDPin, HIGH);
// Wait for remainder of the 10ms cycle = 10000 - 280 - 100 microseconds.
delayMicroseconds(9620);
// Print raw voltage value (number from 0 to 1023).
#ifdef PRINT_RAW_DATA
printValue("VoRaw", VoRaw, true);
Serial.println("");
#endif // PRINT_RAW_DATA
// Use averaging if needed.
float Vo = VoRaw;
#ifdef USE_AVG
VoRawTotal += VoRaw;
VoRawCount++;
if ( VoRawCount >= N ) {
Vo = 1.0 * VoRawTotal / N;
VoRawCount = 0;
VoRawTotal = 0;
} else {
return;
}
#endif // USE_AVG
// Compute the output voltage in Volts.
Vo = Vo / 1024.0 * 5.0;
printFValue("Vo", Vo * 1000.0, "mV");
// Convert to Dust Density in units of ug/m3.
float dV = Vo - Voc;
if ( dV < 0 ) {
dV = 0;
Voc = Vo;
}
float dustDensity = dV / K * 100.0;
printFValue("DustDensity", dustDensity, "ug/m3", true);
Serial.println("");
}
The error when I compile is "expected constructor, destructor, or type conversion before '(' token"
at the line "pinMode(sharpLEDPin, OUTPUT);"