Just Another DIY “Smart” Watch

#include "U8glib.h"

U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_NO_ACK);	// Display which does not send AC

#include <SoftwareSerial.h>
// software serial #1: RX = digital pin 10, TX = digital pin 11
SoftwareSerial bluetooth(10, 11);
#define buflen 10
 char str[buflen+1];
 int strCount=0;


// setup input buffer
#define LINE_MAX 30 
uint8_t line_buf[LINE_MAX] = "Booting...";
uint8_t line_pos = 0;

// setup a text screen to support scrolling
#define ROW_MAX 12


uint8_t screen[ROW_MAX][LINE_MAX];
uint8_t rows, cols;

// line height, which matches the selected font (5x7)
#define LINE_PIXEL_HEIGHT 7

// clear entire screen, called during setup
void clear_screen(void) {
  uint8_t i, j;
  for( i = 0; i < ROW_MAX; i++ )
    for( j = 0; j < LINE_MAX; j++ )
      screen[i][j] = 0;  
}

// append a line to the screen, scroll up
void add_line_to_screen(void) {
  uint8_t i, j;
  for( j = 0; j < LINE_MAX; j++ )
    for( i = 0; i < rows-1; i++ )
      screen[i][j] = screen[i+1][j];
  
  for( j = 0; j < LINE_MAX; j++ )
    screen[rows-1][j] = line_buf[j];
}

// U8GLIB draw procedure: output the screen
void draw(void) {
  uint8_t i, y;
  // graphic commands to redraw the complete screen are placed here    
  y = 0;       // reference is the top left -1 position of the string
  y--;           // correct the -1 position of the drawStr 
  for( i = 0; i < rows; i++ )
  {
    u8g.drawStr( 0, y, (char *)(screen[i]));
    y += u8g.getFontLineSpacing();
  }
}

void exec_line(void) {
  // echo line to the serial monitor
  Serial.println((const char *)line_buf);
  
  // add the line to the screen
  add_line_to_screen();
  
  // U8GLIB picture loop
  u8g.firstPage();  
  do {
    draw();
  } while( u8g.nextPage() );
}

// clear current input buffer
void reset_line(void) { 
      line_pos = 0;
      line_buf[line_pos] = '\0';  
}

// add a single character to the input buffer 
void char_to_line(uint8_t c) {
      line_buf[line_pos] = c;
      line_pos++;
      line_buf[line_pos] = '\0';  
}


void setup(void) {
  Serial.begin(9600);
  bluetooth.begin(9600);
  Serial.print("Hello");
//  bluetooth.println("Hi");
    
//     u8g.firstPage();  
//     u8g.drawStr( 0, 0, "Booting..");
// set font for the console window
  u8g.setFont(u8g_font_5x7);
  //u8g.setFont(u8g_font_9x15);
  
  // set upper left position for the string draw procedure
  u8g.setFontPosTop();
  
  // calculate the number of rows for the display
  rows = u8g.getHeight() / u8g.getFontLineSpacing();
  if ( rows > ROW_MAX )
    rows = ROW_MAX; 
  
  // estimate the number of columns for the display
  cols = u8g.getWidth() / u8g.getStrWidth("m");
  if ( cols > LINE_MAX-1 )
    cols = LINE_MAX-1; 
  
  clear_screen();               // clear screen
  delay(1000);                  // do some delay
  exec_line();                    // place the input buffer into the screen
  reset_line();                   // clear input buffer
}


void loop(void) {
  
   // Keep reading from HC-05 and send to Arduino Serial Monitor
  if (bluetooth.available()){
    char c = bluetooth.read();
    Serial.write(c);
//    uint8_t c;
    
    if ( line_pos >= cols-1 ) {
      exec_line();
      reset_line();
      char_to_line(c);
    } 
    else if ( c == '\n' ) {
      // ignore '\n' 
    }
    else if ( c == '\r' ) {
      exec_line();
      reset_line();
    }
    else {
      char_to_line(c);
    }
}
  if (Serial.available())
    bluetooth.write(Serial.read());

}