/*
 * Arduino Oscilloscope using a graphic LCD
 * The max sampling rates are 4.3ksps with 2 channels and 8.6ksps with a channel.
 * Copyright (c) 2009, Noriaki Mitsunaga
 */

#include <ks0108.h>
#include <Arial14.h>  // font definitions 

#define txtLINE0   0
#define txtLINE1   16
#define txtLINE2   30
#define txtLINE3   46

const int LCD_WIDTH = 128;
const int LCD_HEIGHT = 64;
const int SAMPLES = 100;
const int ad_sw = 3;                    // Analog 3 pin for switches
const int ad_ch0 = 4;                   // Analog 4 pin for channel 0
const int ad_ch1 = 5;                   // Analog 5 pin for channel 1
const unsigned long VREF[] = {49, 98, 244, 488, 976}; // reference voltage 5.0V ->  50 :   1V/div range (100mV/dot)
                                        //                        -> 100 : 0.5V/div
                                        //                        -> 250 : 0.2V/div
                                        //                        -> 500 : 100mV/div
                                        //                       -> 1000 :  50mV/div
const int MILLIVOL_per_dot[] = {100, 50, 20, 10, 5}; // mV/dot
const int MODE_ON = 0;
const int MODE_INV = 1;
const int MODE_OFF = 2;
const char *Modes[] = {"ON", "INV", "OFF"};
const int TRIG_AUTO = 0;
const int TRIG_NORM = 1;
const int TRIG_SCAN = 2;
const int TRIG_ONE  = 3;
const char *TRIG_Modes[] = {"Auto", "Norm", "Scan", "One"};
const int TRIG_E_UP = 0;
const int TRIG_E_DN = 1;
#define RATE_MIN 0
#define RATE_MAX 13
const char *Rates[] = {"F1-1", "F1-2 ", "F2  ", "5ms", "10ms", "20ms", "50ms", "0.1s", "0.2s", "0.5s", "1s", "2s", "5s", "10s"};
#define RANGE_MIN 0
#define RANGE_MAX 4
const char *Ranges[] = {" 1V ", "0.5V", "0.2V", "0.1V", "50mV"};
byte range0 = RANGE_MIN;
byte range1 = RANGE_MIN;
byte ch0_mode = 0, ch1_mode = 0, rate = 5;
byte trig_mode = TRIG_AUTO, trig_lv = 30, trig_edge = TRIG_E_UP, trig_ch = 0;
byte Start = 1, menu = 0;
short ch0_off = 0, ch1_off = 0;
unsigned long startMillis;
byte data[4][SAMPLES];                   // keep twice of the number of channels to make it a double buffer
byte sample=0;                           // index for double buffer

void setup(){
  GLCD.Init(NON_INVERTED);   // initialise the library, non inverted writes pixels onto a clear screen
  GLCD.SelectFont(Arial_14); // you can also make your own fonts, see playground for details  
 
  Serial.begin(9600);
  GLCD.ClearScreen();
  DrawGrid();
  DrawText();
}

void CheckSW() {
  static unsigned short oain[2];
  static unsigned long Millis = 0, oMillis = 0;
  unsigned long ms;
  unsigned short ain = analogRead(ad_sw);
  
  ms = millis();
  if ((ms - Millis)<5)
    return;
  Millis = ms;
  
  if (!(abs(oain[0] - oain[1])>10 && abs(oain[1] - ain)<2)) {
    oain[0] = oain[1];
    oain[1] = ain;
    return;
  }
  oain[0] = oain[1];
  oain[1] = ain;
  
  if (ain > 950 || (Millis - oMillis)<200)
    return;
  oMillis = Millis;

  // Serial.println(ain);
  
  int sw;
  for (sw = 0; sw < 10; sw ++) {
    const int sw_lv[] = {889, 800, 700, 611, 514, 419, 338, 231, 132, 70};
    if (ain > sw_lv[sw])
      break;
  }
  // Serial.println(sw);
  
  switch (menu) {
  case 0:
  default:
    menu0_sw(sw); 
    break;
  case 1:
    menu1_sw(sw); 
    break;
  case 2:
    menu2_sw(sw); 
    break;
  }
  
  DrawText();
}

void menu0_sw(int sw) {  
  switch (sw) {
   case 0:
    // START/HOLD
    if (Start)
       Start = 0;
     else
       Start = 1;
    break;
   case 1:
    // CH0 RANGE -
    if (range0 < RANGE_MAX)
      range0 ++;
    break;
   case 2:
    // CH1 RANGE -
    if (range1 < RANGE_MAX)
      range1 ++;
    break;
   case 3:
    // RATE FAST
    if (rate > 0)
      rate --;
    break;
   case 4:
    // TRIG MODE
    if (trig_mode < TRIG_ONE)
      trig_mode ++;
    else
      trig_mode = 0;
    break;
   case 5:
    // SEND
    SendData();
    break;
   case 6:
    // TRIG MODE
    if (trig_mode > 0)
      trig_mode --;
    else
      trig_mode = TRIG_ONE;
    break;
   case 7:
    // RATE SLOW
    if (rate < RATE_MAX)
      rate ++;
    break;
   case 8:
    // CH1 RANGE +
    if (range1 > 0)
      range1 --;
    break;
   case 9:
    // CH0 RANGE +
    if (range0 > 0)
      range0 --;
    break;
   case 10:
   default:
    // MENU SW
    menu ++;
     break;
  }
}

void menu1_sw(int sw) {  
  switch (sw) {
   case 0:
    // START/HOLD
    if (Start)
       Start = 0;
     else
       Start = 1;
    break;
   case 1:
    // CH0 offset +
    if (ch0_off < 1023)
      ch0_off += 1024/VREF[range0];
    break;
   case 2:
    // CH1 offset +
    if (ch1_off < 1023)
      ch1_off += 1024/VREF[range1];
    break;
   case 3:
    // trigger level +
    if (trig_lv < 60)
      trig_lv ++;
    break;
   case 4:
   case 6:
    // TRIG EDGE
    if (trig_edge == TRIG_E_UP)
      trig_edge = TRIG_E_DN;
    else
      trig_edge = TRIG_E_UP;
    break;
   case 5:
    // SEND
    SendData();
    break;
   case 7:
    // trigger level -
    if (trig_lv > 0)
      trig_lv --;
    break;
   case 8:
    // CH1 OFF -
    if (ch1_off > -1023)
      ch1_off -= 1024/VREF[range1];
    break;
   case 9:
    // CH0 OFF -
    if (ch0_off > -1023)
      ch0_off -= 1024/VREF[range0];
    break;
   case 10:
   default:
    // MENU SW
    menu ++;
     break;
  }
}

void menu2_sw(int sw) {  
  switch (sw) {
   case 0:
    // START/HOLD
    if (Start)
       Start = 0;
     else
       Start = 1;
    break;
   case 1:
    if (ch0_mode < 2)
      ch0_mode ++;
    break;
   case 2:
    if (ch1_mode < 2)
      ch1_mode ++;
    break;
   case 3:
   case 7:
    // TRIG channel
    if (trig_ch == 0)
      trig_ch = 1;
    else
      trig_ch = 0;
    break;
   case 5:
    // SEND
    SendData();
    break;
   case 8:
    if (ch1_mode > 0)
      ch1_mode --;
    break;
   case 9:
    if (ch0_mode > 0)
      ch0_mode --;
    break;
   case 10:
    // MENU SW
    menu = 0;
     break;
   case 4:
   case 6:
   default:
    // none
    break;
  }
}

void SendData() {
  Serial.print(Rates[rate]);
  Serial.println("/div (10 samples)");
  for (int i=0; i<SAMPLES; i ++) {
      Serial.print(data[sample + 0][i]*MILLIVOL_per_dot[range0]);
      Serial.print(" ");
      Serial.println(data[sample + 1][i]*MILLIVOL_per_dot[range1]);
   } 
}

void DrawGrid() {
    for (int x=0; x<=SAMPLES; x += 2) { // Horizontal Line
      for (int y=0; y<=60; y += 10) {
        GLCD.SetDot(x, y, BLACK);
        CheckSW();
      }
    }
    for (int x=0; x<=SAMPLES; x += 10 ) { // Vertical Line
      for (int y=0; y<=60; y += 2) {
        GLCD.SetDot(x, y, BLACK);
        CheckSW();
      }
    }
}

void DrawText() {
    GLCD.FillRect(101,txtLINE0,28,64, WHITE);  // clear text area that will be drawn below 
    
    switch (menu) {
      case 0:
        GLCD.GotoXY(SAMPLES + 1,txtLINE0);         // locate curser for printing text
        GLCD.Puts(Ranges[range0]); 
        GLCD.GotoXY(SAMPLES + 1,txtLINE1);         // locate curser for printing text
        GLCD.Puts(Ranges[range1]); 
        GLCD.GotoXY(SAMPLES + 1,txtLINE2);         // locate curser for printing text
        GLCD.Puts(Rates[rate]); 
        GLCD.GotoXY(SAMPLES + 1,txtLINE3);         // locate curser for printing text
        GLCD.Puts(TRIG_Modes[trig_mode]); 
        break;
      case 1:
        GLCD.GotoXY(SAMPLES + 1,txtLINE0);         // locate curser for printing text
        GLCD.Puts("OF1"); 
        GLCD.GotoXY(SAMPLES + 1,txtLINE1);         // locate curser for printing text
        GLCD.Puts("OF2");
        GLCD.GotoXY(SAMPLES + 1,txtLINE2);         // locate curser for printing text
        GLCD.Puts("Tlv"); 
        GLCD.GotoXY(SAMPLES + 1,txtLINE3);         // locate curser for printing text
        GLCD.Puts(trig_edge == TRIG_E_UP ? "UP" : "DN"); 
        break;
      case 2:
        GLCD.GotoXY(SAMPLES + 1,txtLINE0);         // locate curser for printing text
        GLCD.Puts(Modes[ch0_mode]); 
        GLCD.GotoXY(SAMPLES + 1,txtLINE1);         // locate curser for printing text
        GLCD.Puts(Modes[ch1_mode]);
        GLCD.GotoXY(SAMPLES + 1,txtLINE2);         // locate curser for printing text
        GLCD.Puts(trig_ch == 0 ? "T:1" : "T:2"); 
        break;
    }
}

void DrawGrid(int x) {
    if ((x % 2) == 0)
      for (int y=0; y<=60; y += 10)
        GLCD.SetDot(x, y, BLACK);
    if ((x % 10) == 0)
      for (int y=0; y<=60; y += 2)
        GLCD.SetDot(x, y, BLACK);
}

void ClearAndDrawGraph() {
  int clear = 0;
  
  if (sample == 0)
    clear = 2;
#if 0
   for (int x=0; x<SAMPLES; x++) {
     GLCD.SetDot(x, 60-data[clear+0][x], WHITE);
     GLCD.SetDot(x, 60-data[clear+1][x], WHITE);
     GLCD.SetDot(x, 60-data[sample+0][x], BLACK);
     GLCD.SetDot(x, 60-data[sample+1][x], BLACK);
  }
#else
   for (int x=0; x<(SAMPLES-1); x++) {
     GLCD.DrawLine(x, 60-data[clear+0][x], x+1, 60-data[clear+0][x+1], WHITE);
     GLCD.DrawLine(x, 60-data[clear+1][x], x+1, 60-data[clear+1][x+1], WHITE);
     if (ch0_mode != MODE_OFF)
       GLCD.DrawLine(x, 60-data[sample+0][x], x+1, 60-data[sample+0][x+1], BLACK);
     if (ch1_mode != MODE_OFF)
       GLCD.DrawLine(x, 60-data[sample+1][x], x+1, 60-data[sample+1][x+1], BLACK);
     CheckSW();
  }  
#endif
}

void ClearAndDrawDot(int i) {
  int clear = 0;

  if (i <= 1)
    return;
  if (sample == 0)
    clear = 2;
#if 0
   for (int x=0; x<SAMPLES; x++) {
     GLCD.SetDot(x, 60-data[clear+0][x], WHITE);
     GLCD.SetDot(x, 60-data[clear+1][x], WHITE);
     GLCD.SetDot(x, 60-data[sample+0][x], BLACK);
     GLCD.SetDot(x, 60-data[sample+1][x], BLACK);
  }
#else
  GLCD.DrawLine(i-1, 60-data[clear+0][i-1], i, 60-data[clear+0][i], WHITE);
  GLCD.DrawLine(i-1, 60-data[clear+1][i-1], i, 60-data[clear+1][i], WHITE);
  if (ch0_mode != MODE_OFF)
    GLCD.DrawLine(i-1, 60-data[sample+0][i-1], i, 60-data[sample+0][i], BLACK);
  if (ch1_mode != MODE_OFF)
    GLCD.DrawLine(i-1, 60-data[sample+1][i-1], i, 60-data[sample+1][i], BLACK);
#endif
  DrawGrid(i);
}

void DrawGraph() {
   for (int x=0; x<SAMPLES; x++) {
     GLCD.SetDot(x, 60-data[sample+0][x], BLACK);
     GLCD.SetDot(x, 60-data[sample+1][x], BLACK);
  }
}

void ClearGraph() {
  int clear = 0;
  
  if (sample == 0)
    clear = 2;
  for (int x=0; x<SAMPLES; x++) {
     GLCD.SetDot(x, 60-data[clear+0][x], WHITE);
     GLCD.SetDot(x, 60-data[clear+1][x], WHITE);
  }
}

inline unsigned long adRead(byte ch, byte mode, int off)
{
  unsigned long a = analogRead(ch);
  a = ((a+off)*VREF[ch == ad_ch0 ? range0 : range1]+512) >> 10;
  a = a>=61 ? 60 : a;
  if (mode == MODE_INV)
    return 60 - a;
  return a;
}

void  loop() {
  if (trig_mode != TRIG_SCAN) {
      unsigned long st = millis();
      byte oad;
      if (trig_ch == 0)
        oad = adRead(ad_ch0, ch0_mode, ch0_off);
      else
        oad = adRead(ad_ch1, ch1_mode, ch1_off);
      for (;;) {
        byte ad;
        if (trig_ch == 0)
          ad = adRead(ad_ch0, ch0_mode, ch0_off);
        else
          ad = adRead(ad_ch1, ch1_mode, ch1_off);

        if (trig_edge == TRIG_E_UP) {
           if (ad >= trig_lv && ad > oad)
            break; 
        } else {
           if (ad <= trig_lv && ad < oad)
            break; 
        }
        oad = ad;

        CheckSW();
        if (trig_mode == TRIG_SCAN)
          break;
        if (trig_mode == TRIG_AUTO && (millis() - st) > 100)
          break; 
      }
  }
  
  // sample and draw depending on the sampling rate
    if (rate <= 5 && Start) {
    // change the index for the double buffer
    if (sample == 0)
      sample = 2;
    else
      sample = 0;

    if (rate == 0) { // full speed, channel 0 only
      unsigned long st = millis();
      for (int i=0; i<SAMPLES; i ++) {
        data[sample+0][i] = adRead(ad_ch0, ch0_mode, ch0_off);
      }
      for (int i=0; i<SAMPLES; i ++)
        data[sample+1][i] = 0;
      // Serial.println(millis()-st);
    } else if (rate == 1) { // full speed, channel 1 only
      unsigned long st = millis();
      for (int i=0; i<SAMPLES; i ++) {
        data[sample+1][i] = adRead(ad_ch1, ch1_mode, ch1_off);
      }
      for (int i=0; i<SAMPLES; i ++)
        data[sample+0][i] = 0;
      // Serial.println(millis()-st);
    } else if (rate == 2) { // full speed, dual channel
      unsigned long st = millis();
      for (int i=0; i<SAMPLES; i ++) {
        data[sample+0][i] = adRead(ad_ch0, ch0_mode, ch0_off);
        data[sample+1][i] = adRead(ad_ch1, ch1_mode, ch1_off);
      }
      // Serial.println(millis()-st);
    } else if (rate >= 3 && rate <= 5) { // .5ms, 1ms or 2ms sampling
      const unsigned long r_[] = {500, 1000, 2000};
      unsigned long st0 = millis();
      unsigned long st = micros();
      unsigned long r = r_[rate - 3];
      for (int i=0; i<SAMPLES; i ++) {
        while((st - micros())<r) ;
        st += r;
        data[sample+0][i] = adRead(ad_ch0, ch0_mode, ch0_off);
        data[sample+1][i] = adRead(ad_ch1, ch1_mode, ch1_off);
      }
      // Serial.println(millis()-st0);
    }
    ClearAndDrawGraph();
    CheckSW();
    DrawGrid();
    DrawText();
  } else if (Start) { // 5ms - 500ms sampling
  // copy currently showing data to another
    if (sample == 0) {
      for (int i=0; i<SAMPLES; i ++) {
        data[2][i] = data[0][i];
        data[3][i] = data[1][i];
      }
    } else {
      for (int i=0; i<SAMPLES; i ++) {
        data[0][i] = data[2][i];
        data[1][i] = data[3][i];
      }      
    }

    const unsigned long r_[] = {5000, 10000, 20000, 50000, 100000, 200000, 500000, 1000000};
    unsigned long st0 = millis();
    unsigned long st = micros();
    for (int i=0; i<SAMPLES; i ++) {
      while((st - micros())<r_[rate-6]) {
        CheckSW();
        if (rate<6)
          break;
      }
      if (rate<6) { // sampling rate has been changed
        GLCD.ClearScreen();
        break;
      }
      st += r_[rate-6];
      if (st - micros()>r_[rate-6])
          st = micros(); // sampling rate has been changed to shorter interval
      if (!Start) {
         i --;
         continue;
      }
      data[sample+0][i] = adRead(ad_ch0, ch0_mode, ch0_off);
      data[sample+1][i] = adRead(ad_ch1, ch1_mode, ch1_off);
      ClearAndDrawDot(i);     
    }
    // Serial.println(millis()-st0);
    DrawGrid();
    DrawText();
  } else {
    CheckSW();
  }
  if (trig_mode == TRIG_ONE)
    Start = 0;
}