/* Daisy Chain Number Blocks
**
**  2020-December Maddie Pelz mpelz@mit.edu
**  Code based on example from Scott Lawrence
**
** When activated, the first block in the row will show 1, and then increment and send a higher number to the next block (showing that number on an oled)
**
**  Host--->RX(device 0)TX--->RX(device 1)TX--->RX(device 2)TX--->  Etc
*/
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define OLED_RESET -1
Adafruit_SSD1306 display(128, 64, &Wire, OLED_RESET);

void setup() {
  // initialize serial:
  Serial.begin(9600);
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C); 
  display.clearDisplay(); //for Clearing the display

  display.setTextSize(5);
  display.setTextColor(WHITE);
  display.setCursor(0, 0);
  display.println("Hello"); 
  display.display(); 
  delay(3000);
    
}

void loop()
{
  display.clearDisplay();
  int ch, digit, next_digit;
  
  // wait for something to come in
  if( Serial.available() == 0 ) return;
  // read in a character.
  ch = Serial.read();
  
  if( ch >= '1' && ch <= '3' ) {
    digit = ch - '0';
    display.setTextSize(5);
    display.setTextColor(WHITE);
    display.setCursor(0, 0);
    display.println(digit); 
    display.display(); 
    next_digit = (digit + 1);
    //send digit to oled and then digit plus 1 on to next arduino (or serial output for testing)
    Serial.print(next_digit) + '0';
  }
}