// This version uses bit-banged SPI.
// If you see tearing (jagged edges on the circles) try the version
// which uses AVR's hardware SPI peripheral:
// https://wokwi.com/arduino/projects/318868939929027156

#define CLK 13
#define DIN 11
#define CS  10
#define X_SEGMENTS   4  //x 排幾個 "8x8" (列)
#define Y_SEGMENTS   4  //y 排幾個 "8x8" (行)
#define NUM_SEGMENTS (X_SEGMENTS * Y_SEGMENTS)   //總數共幾個 "8x8"

// a framebuffer to hold the state of the entire matrix of LEDs 
// laid out in raster order, with (0, 0) at the top-left 
// 保存整個 LED 矩陣狀態的幀緩衝區
// 按光柵順序排列，(0, 0) 在左上角
// fb[X] : X= 矩陣總點數 / 8
byte fb[8 * NUM_SEGMENTS];  // 1byte = 8bit , 

byte Hr[]={17,1,
/*--  圖像來源 81SC Hr.bmp  --*/
/*--  寬度x高度18x16  --*/
0xFE,0xFE,0x80,0x80,0x80,0x80,0xFE,0xFE,0x00,0x00,0x60,0xE0,0x80,0x60,0x60,0x60,
0xE0,0xC0,0xFF,0xFF,0x01,0x01,0x01,0x01,0xFF,0xFF,0x00,0x00,0xC0,0xFF,0xC1,0x00,
0x00,0x00,0x01,0x01
};

//MAX7219 DIN傳送方向 --> D0,D1,D2,D3,D4,D5,D6,D7,D8,D9,D10,D11,D12,D13,D14,D15 -->
//D15,D14,D13,D12 : 未使用
//D11,D10,D09,D08 : address
//D07,D06,D05,D04 : HSB Data
//D03,D02,D01,D00 : LSB Data
void MAX72XX_Int(byte send_to_address, byte send_this_data)
{
  digitalWrite(CS, LOW);
  for (int i = 0; i < NUM_SEGMENTS; i++) {
    shiftOut(DIN, CLK, MSBFIRST, send_to_address);
    shiftOut(DIN, CLK, MSBFIRST, send_this_data);
  }
  digitalWrite(CS, HIGH);
}


void setup() {
  Serial.begin(115200);    //設定通訊速率
  pinMode(CLK, OUTPUT);    //設定輸出
  pinMode(DIN, OUTPUT);    //設定輸出
  pinMode(CS, OUTPUT);     //設定輸出

  // Setup each MAX7219   設定 MAX7219
  MAX72XX_Int(0x0c, 0x01); //shutdown register - normal operation 關機寄存器-正常操作
  MAX72XX_Int(0x09, 0x00); //decode mode register - No decode 解碼模式寄存器 - 無解碼
  MAX72XX_Int(0x0a, 0x0f); //intensity register - max brightness 強度寄存器 - 最大亮度
  MAX72XX_Int(0x0b, 0x07); //scan limit register - display digits 0 thru 7 掃描限制寄存器 - 顯示數字 0 到 7
  MAX72XX_Int(0x0f, 0x00); //display test register - test mode off 顯示測試寄存器 - 測試模式關閉
  clear();
}


void loop() {
  

  /*
  static int16_t sx1 = 8<<8, sx2 = sx1, sy1, sy2;
  sx1 = sx1 - (sy1 >> 6);
  sy1 = sy1 + (sx1 >> 6);
  sx2 = sx2 - (sy2 >> 5);
  sy2 = sy2 + (sx2 >> 5);

  static byte travel = 0;
  travel--;
  byte *dst = fb;
  byte output = 0;
  int8_t x_offset = (sx1 >> 8) - X_SEGMENTS * 4;
  int8_t y_offset = (sx2 >> 8) - Y_SEGMENTS * 4;

  uint8_t  screenx, screeny, xroot, yroot;
  uint16_t xsumsquares, ysumsquares, xnextsquare, ynextsquare;
  int8_t   x, y;

  // offset the origin in screen space 在屏幕空間中偏移原點
  x = x_offset;
  y = y_offset;
  ysumsquares = x_offset * x_offset + y * y;  //y 平方和
  yroot = int(sqrtf(ysumsquares));  //y 平方根
  ynextsquare = yroot*yroot;  //y 下一個平方根
//---------------------------------------------------------
  // Quadrant II (top-left)  //第二象限 (左上)
  screeny = Y_SEGMENTS * 8;  //屏幕點 y
  while (y < 0 && screeny) {  //y 小於0 以及 screeny>0
    x = x_offset;
    screenx = X_SEGMENTS * 8; //屏幕點 x
    xsumsquares = ysumsquares;   //x 平方和
    xroot = yroot;            // x平方根
    if (x < 0) {              //如果 x小於0
      xnextsquare = xroot * xroot;  //x 下一個平方根
      while (x < 0 && screenx) {  //x 小於0 以及 screenx>0
        screenx--;
        output <<= 1;
        output |= ((xroot + travel) & 8) >> 3;
        if (!(screenx & 7))
          *dst++ = output;
        xsumsquares += 2 * x++ + 1;
        if (xsumsquares < xnextsquare)
          xnextsquare -= 2 * xroot-- - 1;
      }
    }
//--------------------------------------------------------   
    // Quadrant I (top right) //第一象限 (右上)
    if (screenx) {
      xnextsquare = (xroot + 1) * (xroot + 1);
      while (screenx) {
        screenx--;
        output <<= 1;
        output |= ((xroot + travel) & 8) >> 3;
        if (!(screenx & 7))
          *dst++ = output;
        xsumsquares += 2 * x++ + 1;
        if (xsumsquares >= xnextsquare)
          xnextsquare += 2 * ++xroot + 1;
      }
    }
    ysumsquares += 2 * y++ + 1;
    if (ysumsquares < ynextsquare)
      ynextsquare -= 2 * yroot-- - 1;
    screeny--;
  }

//--------------------------------------------------  
  // Quadrant III (bottom left) //第三象限 (左下)
  ynextsquare = (yroot + 1) * (yroot + 1);
  while (screeny) {
    x = x_offset;
    screenx = X_SEGMENTS * 8;
    xsumsquares = ysumsquares;
    xroot = yroot;
    if (x < 0) {
      xnextsquare = xroot * xroot;
      while (x < 0 && screenx) {
        screenx--;
        output <<= 1;
        output |= ((xroot + travel) & 8) >> 3;
        if (!(screenx & 7))
          *dst++ = output;
        xsumsquares += 2 * x++ + 1;
        if (xsumsquares < xnextsquare)
          xnextsquare -= 2 * xroot-- - 1;
      }
    }
//-------------------------------------------------    
    // Quadrant IV (bottom right) //第四象限 (右下)
    if (screenx) {
      xnextsquare = (xroot + 1) * (xroot + 1);
      while (screenx--) {
        output <<= 1;
        output |= ((xroot + travel) & 8) >> 3;
        if (!(screenx & 7))
          *dst++ = output;
        xsumsquares += 2 * x++ + 1;
        if (xsumsquares >= xnextsquare)
          xnextsquare += 2 * ++xroot + 1;
      }
    }
    ysumsquares += 2 * y++ + 1;
    if (ysumsquares >= ynextsquare)
      ynextsquare += 2 * ++yroot + 1;
    screeny--;
  }
//----------------------------------------------
*/
  byte *dst = Hr;
  byte output = 0;
  /*for (byte i = 0; i < 32; i++)  //1 * NUM_SEGMENTS
    { *dst++ = output; 
       output++; 

    }*/
    GP_Engine(Hr, 0, 2, 0);
    //set_pixel(1, 0, 0xdf);
    while(1)
    {  show();
  delay(10000);}

}

/*
void set_pixel(uint8_t x, uint8_t y, uint8_t mode) {
  byte *addr = &fb[x / 8 + y * X_SEGMENTS];
  byte mask = 128 >> (x % 8);
  switch (mode) {
    case 0: // clear pixel
      *addr &= ~mask;
      break;
    case 1: // plot pixel
      *addr |= mask;
      break;
    case 2: // XOR pixel
      *addr ^= mask;
      break;
  }
}*/ 

void set_pixel(uint8_t x, uint8_t y, uint8_t mode) {
    byte *addr = &fb[x / 8 + y * X_SEGMENTS];
    byte mask = 128 >> (x % 8);
  //byte mask = 128 >> 0;

  byte i,c,rows;
   
  //column=*mode; ++mode;
  //row=*ms; ++ms;

 /* for (i=0; i<=row; i++)
  {
     CSFlag=0;
	   Disp_Position(x1,y1);
     for (j=0; j<=column; j++)
     {
        if (Inverse!=1) c=*ms; else c=~*ms;
        if (x1<61) WriteLeft(1,c);
		else{if (CSFlag==0)	{Disp_Position(x1,y1);CSFlag=1;} WriteRight(1,c);} 
		++ms;++x1;
     } 
     y1++;
	 x1=x;
  }*/
  c=mode;
  rows=0x01; Serial.println(c, BIN);
  for(byte i=0;i<8;i++)
  {
     Serial.println(rows, BIN);
   byte *addr = &fb[x / 8 + (y+i) * X_SEGMENTS];
   if(c & rows) *addr |= mask;
   rows=rows<<1;  
  }

  switch (10) {
    case 0: // clear pixel
      *addr &= ~mask;
      break;
    case 1: // plot pixel
      *addr |= mask;
      byte *addr = &fb[x / 8 + (y+1) * X_SEGMENTS];
      *addr |= mask;
      break;
    case 2: // XOR pixel
      *addr ^= mask;
      break;
  }
}
/*
void safe_pixel(uint8_t x, uint8_t y, uint8_t mode) {
  if ((x >= X_SEGMENTS * 8) || (y >= Y_SEGMENTS * 8))
    return;
  set_pixel(x, y, mode);
}*/

void GP_Engine(unsigned char *ms, char x, char y, char Inverse) 
{ 
  unsigned char CSFlag,i,j,c,row,column,x1,y1;
  x1=x;y1=y;
  column=*ms; ++ms;
  row=*ms; ++ms;
  for (i=0; i<=row; i++)
  {
     CSFlag=0;
     for (j=0; j<=column; j++)
     {
        if (Inverse!=1) c=*ms; else c=~*ms;
        if (x1<61) set_pixel(x1, y1, c);
		//else{if (CSFlag==0)	{CSFlag=1;} set_pixel(x1, y1, c);} 
		++ms;++x1;
     } 
     y1+=8;
	 x1=x;
  }
}

// turn off every LED in the framebuffer
void clear() {
  byte *addr = fb;
  for (byte i = 0; i < 8 * NUM_SEGMENTS; i++)
    *addr++ = 0;
  for (byte row = 0; row < 8; row++) {     // 行: (y軸)
   digitalWrite(CS, LOW);
    byte segment = NUM_SEGMENTS;  // NUM_SEGMENTS=16 
    while (segment--) {
      byte x = segment % X_SEGMENTS;  // X_SEGMENTS=4 ,x =0
      byte y = segment / X_SEGMENTS * 8; // y=32
      byte addr = (row + y) * X_SEGMENTS; //addr=0+32 *4 = 128
      if (segment & X_SEGMENTS) { // odd rows of segments 奇數行段 15,14,13,12 : 7,6,5,4
        shiftOut(DIN, CLK, MSBFIRST, 8 - row);   //傳到 MAX72XX的 addres
        shiftOut(DIN, CLK, LSBFIRST, fb[addr + x]); //傳到 MAX72XX的 data
      } else { // even rows of segments 偶數行段 11,10,9,8 : 3,2,1,0
        shiftOut(DIN, CLK, MSBFIRST, 1 + row);  //傳到 MAX72XX的 addres
        shiftOut(DIN, CLK, MSBFIRST, fb[addr - x + X_SEGMENTS - 1]); //傳到 MAX72XX的 data
      }   
    }
   digitalWrite(CS, HIGH);
  }    
}


// send the raster order framebuffer in the correct order
// for the boustrophedon layout of daisy-chained MAX7219s
// 以正確的順序發送光柵順序幀緩衝區
// 對於菊花鏈 MAX7219s 的 boustrophedon 佈局
// boustrophedon : 不斷地由左向右，由右向左返複書寫的方式
void show() {
  for (byte row = 0; row < 8; row++) {     // 行: (y軸)
    digitalWrite(CS, LOW);
    byte segment = NUM_SEGMENTS;  // NUM_SEGMENTS=16 
    while (segment--) {
      byte x = segment % X_SEGMENTS;  // X_SEGMENTS=4 ,x =0
      byte y = segment / X_SEGMENTS * 8; // y=32
      byte addr = (row + y) * X_SEGMENTS; //addr=0+32 *4 = 128
//digitalWrite(CS, LOW);
      if (segment & X_SEGMENTS) { // odd rows of segments 奇數行段 15,14,13,12 : 7,6,5,4
        shiftOut(DIN, CLK, MSBFIRST, 8 - row);   //傳到 MAX72XX的 addres
        shiftOut(DIN, CLK, LSBFIRST, fb[addr + x]); //傳到 MAX72XX的 data
      } else { // even rows of segments 偶數行段 11,10,9,8 : 3,2,1,0
        shiftOut(DIN, CLK, MSBFIRST, 1 + row);  //傳到 MAX72XX的 addres
        shiftOut(DIN, CLK, MSBFIRST, fb[addr - x + X_SEGMENTS - 1]); //傳到 MAX72XX的 data
      }
//digitalWrite(CS, HIGH);
  // delay(2000);      
    }
    digitalWrite(CS, HIGH);
  }
}