Hi guys,
to be honest, the title is very misleading, but I will explain it.
explain. I am currently building an irrigation system with Hx711 scale
cells. It is well known that multiple HX711s cause problems. I had
hoped that calibrating the scales at full load would allow me to
filter out the interference voltages (if these are responsible for incorrect values
values, as I operate all three hx711s, one 0.96 oled and one dht21
via a 5V power supply) and therefore even if all three
are in operation at the same time.
I had already calibrated all the scales separately, but when I then
the rest of the setup, the values went down the drain.
fell into the stream.
Soooo I wrote a function, which calibrates the scales at every restart.
calibration of the scales one after the other at every restart.
I don't know why, but if I now want to execute this function
function in my void setup, then my Oled display is suddenly no longer recognised
no longer recognised and it cannot output anything.
However, if I exclude the function as it is executed, the display is recognised again. What am I missing?
Thanks guys! Looking forward to some input. slight_smile:
The following code:
#include "DHT.h"
#define DHTPIN A0
#define DHTTYPE DHT21
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Wire.h>
#include "HX711.h"
HX711 scale1;
HX711 scale2;
HX711 scale3;
uint8_t dataPin1 = 5;
uint8_t clockPin1 = 6;
uint8_t dataPin2 = 11;
uint8_t clockPin2 = 12;
uint8_t dataPin3 = 9;
uint8_t clockPin3 = 10;
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
#define OLED_RESET -1 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
DHT dht(DHTPIN, DHTTYPE);
const int PinPump1 = 2;
const int PinPump2 = 3;
const int PinPump3 = 4;
void setup() {
Serial.begin(115200);
if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
Serial.println(F("SSD1306 allocation failed"));
for(;;);
}
delay(2000);
display.clearDisplay();
display.setTextSize(1);
display.setTextColor(WHITE);
// put your setup code here, to run once:
pinMode(PinPump1, OUTPUT); // (pumpe 9) 1 min = 0.2L -> 600000ms = 0.2L -> 30000ms = 0.1L
pinMode(PinPump2, OUTPUT); // (pumpe 10) 1 min = 0.2L
pinMode(PinPump3, OUTPUT); // (pumpe 11) 1 min = 0.2L 1 min = 0.2L
dht.begin();
scale1.begin(dataPin1, clockPin1);
scale2.begin(dataPin2, clockPin2);
scale3.begin(dataPin3, clockPin3);
digitalWrite(PinPump1, HIGH);
digitalWrite(PinPump2, HIGH);
digitalWrite(PinPump3, HIGH);
display.setCursor(0,20);
display.println("Booting shit... dont put shit on!");
display.display();
delay(2000);
display.clearDisplay();
calibration(scale1,1,display);
calibration(scale2,2, display);
calibration(scale3,3, display);
}
void calibration(HX711& scale, int scaleNumber,Adafruit_SSD1306& display) {
const float KNOWN_WEIGHT_GRAMS = 1000.0; // 1kg calibration weight
display.clearDisplay();
display.setCursor(0,0);
display.print("Calibrating #");
display.println(scaleNumber);
// First tare the scale
display.println("Remove all weight");
display.println("and wait...");
display.display();
delay(5000);
scale.set_scale(); // Reset scale factor
scale.tare(); // Reset to zero
display.clearDisplay();
display.println("Place 1kg weight");
display.println("carefully...");
display.display();
delay(5000);
// Take multiple readings for stability
long sum = 0;
int readings = 10;
display.clearDisplay();
display.println("Reading...");
display.println("Don't touch!");
display.display();
for(int i = 0; i < readings; i++) {
sum += scale.get_value();
delay(200);
}
float rawAverage = sum / (float)readings;
float scaleFactor = rawAverage / KNOWN_WEIGHT_GRAMS; // Calculate units per gram
scale.set_scale(scaleFactor);
// Verify calibration
float verifyWeight = scale.get_units(5);
display.clearDisplay();
display.print("Scale #");
display.println(scaleNumber);
display.print("Factor: ");
display.println(scaleFactor);
display.print("Test: ");
display.print(verifyWeight);
display.println("g");
display.display();
delay(3000);
// Store factor in EEPROM here if needed
}
void loop() {
display.clearDisplay();
int w1 = scale1.is_ready() ? scale1.get_units(10) : -1;
delay(100);
int w2 = scale2.is_ready() ? scale2.get_units(10) : -1;
delay(100);
int w3 = scale3.is_ready() ? scale3.get_units(10) : -1;
// Temperature and Humidity Display
float h = dht.readHumidity();
float t = dht.readTemperature();
if (isnan(h) || isnan(t)) {
display.setCursor(0, 0);
display.setTextSize(1);
display.println(F("Failed to read DHT!"));
display.display();
delay(2000);
return;
}
// First Screen: Temperature and Humidity
display.setTextSize(1);
display.setCursor(0,0);
display.print("Temperature: ");
display.setTextSize(2);
display.setCursor(0,10);
display.print(t, 1); // Show one decimal place
display.print(" ");
display.setTextSize(1);
display.cp437(true);
display.write(167);
display.setTextSize(2);
display.print("C");
display.setTextSize(1);
display.setCursor(0, 35);
display.print("Humidity: ");
display.setTextSize(2);
display.setCursor(0, 45);
display.print(h, 1); // Show one decimal place
display.print("%");
display.display();
delay(3000);
// Second Screen: Plant Weights
display.clearDisplay();
display.setTextSize(1);
// Plant 1
display.setCursor(0,0);
display.print("Plant 1: ");
display.print(w1);
display.println("g");
// Plant 2
display.setCursor(0,20);
display.print("Plant 2: ");
display.print(w2);
display.println("g");
// Plant 3
display.setCursor(0,40);
display.print("Plant 3: ");
display.print(w3);
display.println("g");
display.display();
delay(2000);
// In the pump sections, ensure all display updates are followed by display.display():
if (w1 > 4000) {
// Do nothing
} else {
unsigned long startTime = millis(); // Record the start time
unsigned long timeout = 3000; // Timeout after 30 seconds
while (w1 < 1) {
display.setCursor(0,10);
display.print("Pumpe 1 läuft...");
display.display(); // Make sure this is present
digitalWrite(PinPump1, LOW); // Turn on pump
delay(2000);
w1 = scale1.get_value(10);
display.clearDisplay(); // Read new weight after irrigation
if (millis() - startTime > timeout) {
display.setCursor(0,10);
display.print("Timeout reached! Stopping pump.");
display.display();
delay(2000);
display.clearDisplay();
break;
}
}
digitalWrite(PinPump1, HIGH); // Turn off pump
}
display.clearDisplay();
if (w2 > 1) {
// Do nothing, don't turn on the pump
} else {
unsigned long startTime = millis(); // Record the start time
unsigned long timeout = 3000; // Timeout after 30 seconds
while (w2 < 7000) {
display.setCursor(0,10);
display.print("Pumpe 2 läuft...");
display.display(); // Loop until weight reaches 7000
digitalWrite(PinPump2, LOW); // Turn on pump
delay(2000);
w2 = scale2.get_value();
display.clearDisplay(); // Read new weight after irrigation
if (millis() - startTime > timeout) {
display.setCursor(0,10);
display.print("Timeout reached! Stopping pump.");
display.display();
delay(2000);
display.clearDisplay();
break;
}
}
digitalWrite(PinPump2, HIGH); // Turn off pump
}
display.clearDisplay();
if (w3 > 1) {
// Do nothing, don't turn on the pump
} else {
unsigned long startTime = millis(); // Record the start time
unsigned long timeout = 3000; // Timeout after 30 seconds
while (w3 < 7000) {
display.setCursor(0,10);
display.print("Pumpe 3 läuft...");
display.display(); // Loop until weight reaches 7000
digitalWrite(PinPump3, LOW); // Turn on pump
delay(2000);
w3 = scale3.get_value();
display.clearDisplay(); // Read new weight after irrigation
if (millis() - startTime > timeout) {
display.setCursor(0,10);
display.print("Timeout reached! Stopping pump.");
display.display();
delay(2000);
display.clearDisplay();
break;
}
}
digitalWrite(PinPump3, HIGH); // Turn off pump
}
display.clearDisplay();
}
