/*=================================================================
# Project : I2C OLED (SSD1306)
#         : 
# Date    : 2021-04-09
# Version : 1.3
#
# Note:
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY : without even the implied warranty of 
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE
#
# Board : Raspberry Pi Pico
# IDE   : Arduino IDE
# Library :
#     Adafruit_SSD1306 : https://github.com/adafruit/Adafruit_SSD1306
#     Adafruit_GFX     : https://github.com/adafruit/Adafruit-GFX-Library
#=================================================================*/
 
#include <Wire.h>
#include <SPI.h>
 
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Fonts/FreeSans12pt7b.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 // i2c slave address
Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

 
 
 //=======================================================================
void setup()
{
 

  Serial.begin(115200);
//  Wire.setSDA(16);
//  Wire.setSCL(17);
  Wire.begin();
  Wire.setClock(400000); //400kHz

  delay(10000);
 
  // SSD1306_SWITCHCAPVCC = generate display voltage from 3.3V internally
  if(!oled.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); // Don't proceed, loop forever
  }

  // Show initial display buffer contents on the screen --
  // the library initializes this with an Adafruit splash screen.
  oled.display();
  delay(2000); // Pause for 2 seconds

 
}
 

//=======================================================================
void test(void) 
{
//   float v = 0.0;
   float v = analogRead(A0);
   Serial.print("Value: ");
   Serial.println(v);

//String myStr;
//myStr = String(v); 
   
//   delay(500); 
    
    oled.clearDisplay();
    oled.setTextSize(1);      // Normal 1:1 pixel scale
    oled.setTextColor(SSD1306_WHITE); // Draw white text
    oled.cp437(true);         // Use full 256 char 'Code Page 437' font    
    oled.setFont(&FreeSans12pt7b);

    oled.drawRect(0, 0, SCREEN_WIDTH-1,SCREEN_HEIGHT-1 , SSD1306_WHITE);
    oled.setCursor(10, 25);   
    oled.write("Value:");
    oled.setCursor(10, 50);
    oled.print(String(v));
    
    oled.display();
//    delay(2000);
}


//=======================================================================
 void loop() 
 {
// Sensorwerte:    
//   int Value = analogRead(26);
//   Serial.print("Value: ");
//   Serial.println(Value);
//   delay(500); 
    
    
    
    test();
//    delay(3000);
    oled.clearDisplay();
    oled.display();
//    delay(3000);
}