Analog pins affecting stuff

Other Hardware Sensors
1 
#include <Arduino.h>
#include <SPI.h>
#include <RF24.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
const int Bat = A0; //r1=1000ohme r2=1250ohme
#define joyX A6
#define joyY A7
int arrbtn[] = {3, 4, 5};
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
#define OLED_RESET     -1 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

int spd=0;
int trn=0;
bool joy=false;
bool bt1 = false;
bool bt2 = false;
bool bt3 = false;
RF24 radio(10, 9); // ce/cs
bool isTransmitter = true; // if true, device starts as transmitter

void setup() {
  pinMode(A6, INPUT);
  pinMode(A7, INPUT);
    pinMode(A0, INPUT);

for (int i = 0; i < 3; i++) {
    pinMode(arrbtn[i], INPUT_PULLUP);
  }

    if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { 
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
 // delay(2000);
  display.clearDisplay();

  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(30, 30);
  // Display static text
  display.println("R.O.B.E.R.T.O");
  display.display(); 
 // delay(2000);

   display.display(); 
  Serial.begin(9600);
  radio.begin();
  radio.openWritingPipe(00002); // needs to be opposite on the other device
  radio.setPALevel(RF24_PA_HIGH); //   ^
  radio.openReadingPipe(1, 000001); // |
  radio.startListening();
}
float extractDecimalNumber(const char* text) {
    float result = 0.0;
    float sign = 1.0;  // Positive by default
    int i = 3;  // Start from the fourth character after "bat"
    bool decimalPoint = false;
    float divisor = 10.0;

    if (text[i] == '-') {
        sign = -1.0;
        i++;
    }

    while (text[i] != '\0') {
        if (text[i] >= '0' && text[i] <= '9') {
            if (decimalPoint) {
                result += (text[i] - '0') / divisor;
                divisor *= 10.0;
            } else {
                result = result * 10.0 + (text[i] - '0');
            }
        } else if (text[i] == '.') {
            decimalPoint = true;
        } else {
            // Handle other characters or break on non-numeric characters if needed.
            break;
        }
        i++;
    }

    return sign * result;
}
void handleTransmitterMode() {
  //Serial.println("in tran mode");
  radio.stopListening(); // turns radio into transmitter
delay(10);
  char text[] = "Change"; // converts the text "change" into an array under the name text
  radio.write(&text, sizeof(text)); // radio sends the message and the size of the message
//  Serial.println("Transmitted message");
  isTransmitter = false; // toggles transmitter role
}
float batc = 0;
void handleReceiverMode() {
  //Serial.println("in rev mode");
  radio.startListening(); // toggles radio into receiver mode
  if (radio.available()) {
    char text[32] = ""; // clears the 32 byte variable known as "text"
    radio.read(&text, sizeof(text)); // reads the transmission
    Serial.print("Received message: ");
    Serial.println(text);
    if (strncmp(text, "bat", 3) == 0) {
      Serial.println(extractDecimalNumber(text));
      batc = extractDecimalNumber(text);
    }
  }
  else {
    // This section only runs if no "bat" message was received.
    radio.startListening(); // toggles radio into receiver mode
    if (radio.available()) {
      char text2[32] = ""; // Use a different variable name for the second text buffer
      radio.read(&text2, sizeof(text2)); // reads the transmission
      Serial.print("Received message: ");
      Serial.println(text2);
      if (strcmp(text2, "Change") == 0) { // checks if the transmission is "change", if it is
        isTransmitter = true; // then toggle
        Serial.println("jayveer");
        delay(100);
      }
    }
  }
}

void joystick() {
  int xValue = analogRead(joyX) - 512;
  int yValue = analogRead(joyY) - 515;
   for (int i = 0; i < 31; i++) {
    if (digitalRead(arrbtn[i]) == LOW) {
        switch (i)
  {
  case 0:
//autodrive
  bt1 = !bt1;
  {
   radio.stopListening(); 
   char b1[] = "b1";
  radio.write(&b1, sizeof(b1)); 
  Serial.println("b1");
  isTransmitter = true;
}
    break;

    case 1:
  bt2 = !bt2;
  {
   radio.stopListening(); 
   char b2[] = "b2";
  radio.write(&b2, sizeof(b2)); 
  Serial.println("b2");
  isTransmitter = true;
}
    break;


      case 2:
  bt3 = !bt3;
  {
   radio.stopListening(); 
   char b3[] = "b3";
  radio.write(&b3, sizeof(b3)); 
  Serial.println("b3");
  isTransmitter = true;
}
    break;

  }
    }
  }

  // Perform any additional joystick-related actions here
  if (xValue > 15 || yValue > 15 || xValue < -15 || yValue < -15) {
    joy=true;
  spd=xValue;
  trn=yValue;
  radio.stopListening(); 

  String trnT = "trn" + String(trn);
  radio.write(trnT.c_str(), trnT.length() + 1); // +1 to include null terminator
  Serial.println(trnT);

  String spdT = "spd" + String(spd);
  radio.write(spdT.c_str(), spdT.length() + 1); // +1 to include null terminator
  Serial.println(spdT);
  isTransmitter = true;
  }
  else if(isTransmitter){  char text[] = "Change"; 
  radio.write(&text, sizeof(text)); 
  Serial.println("this");
  joy=false;}

}
void kill(){

   radio.stopListening(); 
   char text1[] = "Zero";
  radio.write(&text1, sizeof(text1)); 
  //Serial.println("Zero");
  }


void LCD() {
  int xValue = analogRead(joyX) - 512;
  int yValue = analogRead(joyY) - 515;

  int rawValue = analogRead(Bat);
  float batteryVoltage = (float)rawValue * (9.0 / 1023.0);
  float batteryPercentage = map(batteryVoltage, 0.0, 9.0, 0, 100);
  display.setTextSize(1);
  display.clearDisplay();
  display.setCursor(0, 0);
  display.println("CB% : ");
  display.println(batteryPercentage);

  display.setCursor(90, 0);
  display.println("DB% :");
  display.setCursor(90, 9);
  display.println(batc);
  display.display();
  display.display();
  display.drawRect(55, 0, 18, 16, WHITE);
  display.display();
  if(xValue>35){
  display.setTextSize(2);
  display.setCursor(10, 20);
  display.print("FWRD  ");
  display.print(xValue/2);
  display.display();
  }
  else if(xValue<-35){
  display.setTextSize(2);
  display.setCursor(10, 20);
  display.print("BKWD ");
  display.print(xValue/2);
  display.display();
  }
    if(yValue>35){
  display.setTextSize(2);
  display.setCursor(10, 40);
  display.print("RGHT  ");
  display.print(yValue/2);
  display.display();
  }
  else if(yValue<-35){
  display.setTextSize(2);
  display.setCursor(10, 40);
  display.print("LEFT ");
  display.print(yValue/2);
  display.display();
  }
}


void loop() {

  LCD();
    joystick();
  if(!joy){
    kill();
  }
  // Only execute transmitter or receiver functions when the joystick is not being used
  if (isTransmitter && !joy) {
    handleTransmitterMode(); // if transmitter is true, go to that function
  } else if (!isTransmitter && !joy) {
    handleReceiverMode(); // if transmitter is false, go to that function
  }
if(bt1){
  display.setTextSize(2);
  display.setCursor(60, 0);
  display.println("1");
   display.display();
  }
  if(bt2){
  display.setTextSize(2);
  display.setCursor(60, 0);
  display.println("2");
   display.display();
  }
  if(bt3){
  display.setTextSize(2);
  display.setCursor(60, 0);
  display.println("3");
   display.display();
  }
   }

this code all works fine, except for the fact that my battery percentage of the controller "cb" changes values with the joystick, but only on the x axis.

void setup() {
  pinMode(A6, INPUT);
  pinMode(A7, INPUT);
    pinMode(A0, INPUT);
Serial.begin(9600);
}

void loop() {
  analogRead(A6);
  analogRead(A7);
  int rawValue = analogRead(A0);
  float batteryVoltage = (float)rawValue * (9.0 / 1023.0);
  float batteryPercentage = map(batteryVoltage, 0.0, 9.0, 0, 100);
  Serial.println(batteryPercentage);

}

I tried this, and the exact same thing happens. Im using a voltage divider on a 9v battery, 1000 ohme r1 and 1220 r2. battery percentage with the joystick unplugged is 66%, as soon as i plug it in, it drops to 55%, and then when i move along the x axis it goes up +-30%.

2

There's actually only 1 ADC (and one sample and hold cap) in the ATMega328. There's an 8 channel analog mux in front of it. So if you're reading different channels in succession, it takes time for the value on the sample and hold cap to change - and the higher the resistances on the current input, the longer it takes.

Trying adding an external cap to ground of, oh, 0.1uF to your A0 input. If this is the problem, that should help.

3

thank you so much!

4

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