Hello I have a project wherein I need to send data from uno to nodemcu and then the values will be sent to blynk. My issue is that when using software serial it worked the day before now the nodemcu is not receiving the data or showing anything at all at it's serial monitor. Help please I'm now confused as I have no idea why this keeps on happening.
arduino code:
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <SoftwareSerial.h>
// Constants for sensor pins
const int AMMONIA_SENSOR_PIN = A0;
const int CO2_SENSOR_PIN = A1;
// Constants for relay pins
const int RELAY1_PIN = 4;
const int RELAY2_PIN = 5;
const int RELAY3_PIN = 6;
// Constants for calculation
const float SENSOR_VOLTAGE_REF = 5.0;
const float ADC_RESOLUTION = 1023.0;
const float M = -0.263; // Slope
const float B = 0.42; // Y-Intercept
const float R0 = 35; // Sensor resistance in fresh air
// SoftwareSerial setup
SoftwareSerial mySerial(2, 3); // RX, TX pins on Arduino Uno
// LCD setup
LiquidCrystal_I2C lcd(0x27, 16, 2); // LCD address and size
void setup() {
initializeSensorsAndRelays();
initializeLCD();
initializeSerial();
}
void loop() {
double ammonia_ppm = readAmmoniaLevel();
int co2Level = readCO2Level();
controlRelays(ammonia_ppm);
displaySensorReadings(ammonia_ppm, co2Level);
sendReadingsToNodeMCU(ammonia_ppm, co2Level);
// Print readings to Serial Monitor
Serial.print("Ammonia: ");
Serial.print(ammonia_ppm, 2);
Serial.print(" ppm\t");
Serial.print("CO2: ");
Serial.print(co2Level);
Serial.println(" ppm");
delay(500); // Delay for stability - consider non-blocking alternatives
}
void initializeSensorsAndRelays() {
pinMode(CO2_SENSOR_PIN, INPUT);
pinMode(AMMONIA_SENSOR_PIN, INPUT);
pinMode(RELAY1_PIN, OUTPUT);
pinMode(RELAY2_PIN, OUTPUT);
pinMode(RELAY3_PIN, OUTPUT);
digitalWrite(RELAY1_PIN, LOW);
digitalWrite(RELAY2_PIN, LOW);
digitalWrite(RELAY3_PIN, LOW);
}
void initializeLCD() {
lcd.init();
lcd.backlight();
}
void initializeSerial() {
Serial.begin(115200); // Changed baud rate to 115200
mySerial.begin(115200);
}
double readAmmoniaLevel() {
int sensorValue = analogRead(AMMONIA_SENSOR_PIN);
double sensorVolt = sensorValue * (SENSOR_VOLTAGE_REF / ADC_RESOLUTION);
double RS_gas = ((SENSOR_VOLTAGE_REF * 10.0) / sensorVolt) - 10;
double ratio = RS_gas / R0;
return pow(10, (log10(ratio) - B) / M);
}
int readCO2Level() {
int gas = analogRead(CO2_SENSOR_PIN);
return map(gas - 64, 0, 1024, 400, 5000);
}
void controlRelays(double ammoniaPpm) {
if (ammoniaPpm >= 2 && ammoniaPpm <= 10) {
digitalWrite(RELAY1_PIN, LOW);
} else {
digitalWrite(RELAY1_PIN, HIGH);
}
if (ammoniaPpm > 10 && ammoniaPpm <= 20) {
digitalWrite(RELAY2_PIN, LOW);
} else {
digitalWrite(RELAY2_PIN, HIGH);
}
if (ammoniaPpm > 20 && ammoniaPpm <= 50) {
digitalWrite(RELAY3_PIN, LOW);
} else {
digitalWrite(RELAY3_PIN, HIGH);
}
delay(500); // Delay outside the if statements to avoid unnecessary repetition
}
void displaySensorReadings(double ammonia_ppm, double co2Level) {
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Ammonia: ");
lcd.print(ammonia_ppm, 2);
lcd.setCursor(0, 1);
lcd.print("CO2: ");
lcd.print(co2Level);
}
void sendReadingsToNodeMCU(double ammonia_ppm, double co2Level) {
mySerial.print(ammonia_ppm, 2);
mySerial.print(",");
mySerial.println(co2Level);
delay(1000);
}
nodemcu code:
#define BLYNK_TEMPLATE_ID "TMPL64qpH6bPb"
#define BLYNK_TEMPLATE_NAME "mq137"
#define BLYNK_AUTH_TOKEN "zeFfyjNsRBwxi2LXwTTR2ZQ2njAa9F8p"
#define BLYNK_PRINT Serial
#include <ESP8266WiFi.h>
#include <SoftwareSerial.h>
#include <BlynkSimpleEsp8266.h>
char auth[] = "zeFfyjNsRBwxi2LXwTTR2ZQ2njAa9F8p"; // Replace with your Blynk Auth Token
char ssid[] = "qwe"; // Replace with your Wi-Fi SSID
char pass[] = "nayeonnnie"; // Replace with your Wi-Fi Password
SoftwareSerial nodemcuSerial(D7, D8); // RX, TX pins on NodeMCU
BlynkTimer timer;
void myTimer() {
while (nodemcuSerial.available()) {
String data = nodemcuSerial.readStringUntil('\n');
// Split the received data into ammonia and CO2 values
int commaIndex = data.indexOf(',');
String ammoniaValue = data.substring(0, commaIndex);
String co2Value = data.substring(commaIndex + 1);
float ppmValueAmmonia = ammoniaValue.toFloat();
float ppmValueCO2 = co2Value.toFloat();
Blynk.virtualWrite(V0, ppmValueAmmonia); // Send the ammonia ppm value to V0
Blynk.virtualWrite(V1, ppmValueCO2); // Send the CO2 ppm value to V1
Serial.print("Received ppm values - Ammonia: ");
Serial.print(ppmValueAmmonia);
Serial.print(", CO2: ");
Serial.println(ppmValueCO2); // Print ppm values to the serial monitor
delay(1000);
}
}
void setup() {
Serial.begin(115200);
Blynk.begin(auth, ssid, pass);
nodemcuSerial.begin(115200);
timer.setInterval(1000L, myTimer);
}
void loop() {
Blynk.run();
timer.run();
}
