/* ------------------------------------------------------------------------------------
 *  Skeleton project for setting up ATTiny85 with an OLED SSD1306
 *  Basic display function for numbers
 *  Auth:     EA
 *  Last rev: 2023-12-29
 * ------------------------------------------------------------------------------------
*/ 
#include <TinyWireM.h>
#include "SSD1306_config.h"

// Sparkfun: P1 - 1
const byte SPEAKER_PIN = 1;   // 0 = Pin 8, 4 = Pin 3
const byte BTN_PIN = 4;

// Not PROGMEMming this right now
byte digits[10][4] =
{
	{ 0x7e, 0x81, 0x81, 0x7e },
	{ 0x82, 0xff, 0x80, 0x00 },
	{ 0xc2, 0xa1, 0x91, 0x8f },
	{ 0x42, 0x91, 0x91, 0x6e },
	{ 0x1f, 0x10, 0x10, 0xff },
	{ 0x4f, 0x91, 0x91, 0x61 },
	{ 0x7c, 0x92, 0x91, 0x61 },
	{ 0x01, 0xf1, 0x09, 0x07 },
	{ 0x6e, 0x91, 0x91, 0x6e },
	{ 0x0e, 0x91, 0x51, 0x3e }
};


// ------------------------------------------------------------------------------------
//    SETUP
// ------------------------------------------------------------------------------------
void setup() {
  TinyWireM.begin();
  config_display();

  pinMode(SPEAKER_PIN, OUTPUT);

  cursorTo(0,0);
  send_data(0b11001100);
  send_data(0b00110011);
  send_data(0b11001100);
  send_data(0b00110011);
  send_data(0b11001100);
  send_data(0b00110011);
  delay(1000);

}


// ------------------------------------------------------------------------------------
//    LOOP
// ------------------------------------------------------------------------------------
void loop() {

  beep(420, 50);
  
  displayNumberAt(10, 10, 1);
  delay(1000);
  displayNumberAt(10, 10, 23);
  delay(1000);
  displayNumberAt(10, 10, 856);
  delay(1000);
  displayNumberAt(10, 10, 1000);
  delay(1000);
  displayNumberAt(10, 10, 9876);
  delay(1000);
  displayNumberAt(10, 10, 543);
  delay(1000);
  displayNumberAt(10, 10, 210);
  delay(1000);
  displayNumberAt(10, 10, 0001);
  delay(1000);

}



void displayNumberAt(uint8_t x, uint8_t y, int number) {

  beep(660, 40);

  cursorTo(x, y);

  // Count number of digits 
  int c = 0; // Digit position 
  int n = number;

  while (n != 0) {
      n /= 10;
      c++;
  }

  int numberArray[c];
  c = 0;    
  n = number;

  // Extract each digit 
  while (n != 0) {
      numberArray[c] = n % 10;
      n /= 10;
      c++;
  }

  // Send digit data, end with space (0x00).  
  for (uint8_t i=0; i<c; i++) {
    send_data(digits[numberArray[c-i-1]][0]);
    send_data(digits[numberArray[c-i-1]][1]);
    send_data(digits[numberArray[c-i-1]][2]);
    send_data(digits[numberArray[c-i-1]][3]);
    send_data(0x00);

    /*
    // This is probably faster.
    TinyWireM.beginTransmission(0x3C);
    TinyWireM.write(0x40);            // data mode
    TinyWireM.write( digits[numberArray[c-i-1]][0] );
    TinyWireM.write( digits[numberArray[c-i-1]][1] );
    TinyWireM.write( digits[numberArray[c-i-1]][2] );
    TinyWireM.write( digits[numberArray[c-i-1]][3] );
    TinyWireM.write( 0x00 );
    TinyWireM.endTransmission();
    */
  }
}

void beep (int frequencyInHertz, byte timeInMilliseconds)
{  
  int delayAmount = (long)(1000000 / frequencyInHertz);
  int loopTime = (int)((timeInMilliseconds*10) / (delayAmount * 0.002));
  
  for (int x = 0; x < loopTime; x++) {
    digitalWrite(SPEAKER_PIN, HIGH);
    delayMicroseconds(delayAmount);
    digitalWrite(SPEAKER_PIN, LOW);
    delayMicroseconds(delayAmount);
  }  
}

void cursorTo(byte x, byte page) {
  send_command(0x22);
  send_command(page);
  send_command(7);
  send_command(0x21);
  send_command(x);
  send_command(127);
}



void config_display() {
  for(int i=0; i<sizeof(initializeCmds); i++) {
    send_command(pgm_read_byte(initializeCmds+i));
  }
}

void send_command(unsigned char cmd) {
  TinyWireM.beginTransmission(0x3c);
  TinyWireM.write(0x00);
  TinyWireM.write(cmd);
  TinyWireM.endTransmission();
}

void send_data(byte slice) {
  TinyWireM.beginTransmission(0x3C);
  TinyWireM.write(0x40);
  TinyWireM.write(slice);
  TinyWireM.endTransmission();
}