LCD displaying pin voltage level

Other Hardware Displays
1 
#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#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)
// The pins for I2C are defined by the Wire-library. 
// On an arduino UNO:       A4(SDA), A5(SCL)
// On an arduino MEGA 2560: 20(SDA), 21(SCL)
// On an arduino LEONARDO:   2(SDA),  3(SCL), ...
#define OLED_RESET     -1 // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_ADDRESS 0x3C ///< See datasheet for Address; 0x3D for 128x64, 0x3C for 128x32
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
void setup() {
Serial.begin(9600);
 if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
display.display();
delay(2000); // Pause for 2 seconds

// Clear the buffer
display.clearDisplay();

}}

void loop() {
int sensorValue = analogRead(A0);
float voltage = sensorValue * (5.0 / 1023.0);
lcd.print(voltage);
delay(100)

Getting error about the "lcd" part of "lcd.print" not being declared. I'm new to the Adafruit library and Arduino so I don't know the exact procedure or syntax. Just looking to display in plain text the voltage read from the pin.

Thanks

2

You are missing a brace }

Does an example from the library compile ?

3

brace is in the code I just failed to copy it over :sweat_smile:
Yes, example complies and display on screen

4

Try:

display.println(F("Hello, world!"));

5

The object name assigned to the screen is "display", so use

display.print(voltage);
display.display();

Study the examples carefully, as well as the documentation.

6

I'm getting the logo buffer to appear from my setup section but then not getting anything afterwards.

7

After logo buffer in void setup I'm not getting anything

8

Then there are mistakes in the revised code, which you forgot to post.

9 
#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#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)
// The pins for I2C are defined by the Wire-library. 
// On an arduino UNO:       A4(SDA), A5(SCL)
// On an arduino MEGA 2560: 20(SDA), 21(SCL)
// On an arduino LEONARDO:   2(SDA),  3(SCL), ...
#define OLED_RESET     -1 // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_ADDRESS 0x3C ///< See datasheet for Address; 0x3D for 128x64, 0x3C for 128x32
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

static const unsigned char PROGMEM logo_bmp[] =
{ 0b00000000, 0b11000000,
  0b00000001, 0b11000000,
  0b00000001, 0b11000000,
  0b00000011, 0b11100000,
  0b11110011, 0b11100000,
  0b11111110, 0b11111000,
  0b01111110, 0b11111111,
  0b00110011, 0b10011111,
  0b00011111, 0b11111100,
  0b00001101, 0b01110000,
  0b00011011, 0b10100000,
  0b00111111, 0b11100000,
  0b00111111, 0b11110000,
  0b01111100, 0b11110000,
  0b01110000, 0b01110000,
  0b00000000, 0b00110000 };
  
void setup() {
Serial.begin(9600);
 if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);}
display.display();
delay(2000); // Pause for 2 seconds

// Clear the buffer
display.clearDisplay();

}

void loop() {
display.print(F("Hello, world!"));
int sensorValue = analogRead(A0);
float voltage = sensorValue * (5.0 / 1023.0);
Serial.println(voltage);
display.print(voltage);
display.display();
delay(100);
}

Revised code. New to forum posting sorry :sweat_smile:

10 
  Serial.println(voltage);
  display.setTextSize(1);             // Normal 1:1 pixel scale
  display.setTextColor(SSD1306_WHITE);        // Draw white text
  display.setCursor(0,0);
  display.print(voltage);
  display.display();
11

Works great thank you! Added in a clear display so that the values didn't write on top of each other.

12

First off. God provided you with a formatting key in the IDE. i.e. ctrl-T
It makes your code (and bugs) easier to read.

void setup() {
    Serial.begin(9600);
    if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
        Serial.println(F("SSD1306 allocation failed"));
        for (;;);
    }
    display.display();
    delay(2000); // Pause for 2 seconds

    // Clear the buffer
    display.clearDisplay();

}

void loop() {
    display.print(F("Hello, world!"));
    int sensorValue = analogRead(A0);
    float voltage = sensorValue * (5.0 / 1023.0);
    Serial.println(voltage);
    display.print(voltage);
    display.display();
    delay(100);
}

Sure enough. You see Adafruit logo. Then a blank screen.

Add these lines to your loop()

void loop() {
    display.clearDisplay();       //start with fresh screen
    display.setTextColor(WHITE);  //otherwise BLACK text does not show up
    display.setCursor(0, 0);      //otherwise the cursor falls off the screen
    display.print(F("Hello, world!"));
13

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