Sketch seems to be skipping data

Projects Programming
26

david_2018 -

Thank you for this. I plugged it in, and it works. And for those who want to see this for the TFT, I've got the sketch below. One thing I did run into was that when it gets below 10, the digits shift to the left one place, since there is no longer a ones column, which in my case, I don't want that anyway, so I had to add a couple if statements to add " " or " 0" if the value was less than 10 or less than 0.

Note that I took an example sketch for the TFT display, and modified it to test this out, so it might need a little cleaning up around the edges.

#include <Elegoo_GFX.h>    // Core graphics library
#include <Elegoo_TFTLCD.h> // Hardware-specific library

#define LCD_CS A3 // Chip Select goes to Analog 3
#define LCD_CD A2 // Command/Data goes to Analog 2
#define LCD_WR A1 // LCD Write goes to Analog 1
#define LCD_RD A0 // LCD Read goes to Analog 0

#define LCD_RESET A4 // Can alternately just connect to Arduino's reset pin

// Assign human-readable names to some common 16-bit color values:
#define  BLACK   0x0000
#define BLUE    0x001F
#define RED     0xF800
#define GREEN   0x07E0
#define CYAN    0x07FF
#define MAGENTA 0xF81F
#define YELLOW  0xFFE0
#define WHITE   0xFFFF
int Value1;
int Value2;
int OldValue1;
int OldValue2;
float Volts;
int Tenths;
int Ones;
int Tens;
int OldTens;
int OldOnes;
int OldTenths;
float PresentVolts;

Elegoo_TFTLCD tft(LCD_CS, LCD_CD, LCD_WR, LCD_RD, LCD_RESET);

void setup(void) {
  Serial.begin(9600);
  Serial.println(F("TFT LCD test"));

#ifdef USE_Elegoo_SHIELD_PINOUT
  Serial.println(F("Using Elegoo 2.4\" TFT Arduino Shield Pinout"));
#else
  Serial.println(F("Using Elegoo 2.4\" TFT Breakout Board Pinout"));
#endif

  Serial.print("TFT size is "); Serial.print(tft.width()); Serial.print("x"); Serial.println(tft.height());

  tft.reset();

  uint16_t identifier = tft.readID();
  if (identifier == 0x9325) {
    Serial.println(F("Found ILI9325 LCD driver"));
  } else if (identifier == 0x9328) {
    Serial.println(F("Found ILI9328 LCD driver"));
  } else if (identifier == 0x4535) {
    Serial.println(F("Found LGDP4535 LCD driver"));
  } else if (identifier == 0x7575) {
    Serial.println(F("Found HX8347G LCD driver"));
  } else if (identifier == 0x9341) {
    Serial.println(F("Found ILI9341 LCD driver"));
  } else if (identifier == 0x8357) {
    Serial.println(F("Found HX8357D LCD driver"));
  } else if (identifier == 0x0101)
  {
    identifier = 0x9341;
    Serial.println(F("Found 0x9341 LCD driver"));
  }
  else if (identifier == 0x1111)
  {
    identifier = 0x9328;
    Serial.println(F("Found 0x9328 LCD driver"));
  }
  else {
    Serial.print(F("Unknown LCD driver chip: "));
    Serial.println(identifier, HEX);
    Serial.println(F("If using the Elegoo 2.8\" TFT Arduino shield, the line:"));
    Serial.println(F("  #define USE_Elegoo_SHIELD_PINOUT"));
    Serial.println(F("should appear in the library header (Elegoo_TFT.h)."));
    Serial.println(F("If using the breakout board, it should NOT be #defined!"));
    Serial.println(F("Also if using the breakout, double-check that all wiring"));
    Serial.println(F("matches the tutorial."));
    identifier = 0x9328;

  }
  tft.begin(identifier);

  Value1 = 100;
  Value2 = 200;
  tft.setRotation(3);
  tft.fillScreen(BLACK);
  unsigned long start = micros();

  Volts = 15.0;
}

void loop(void) {

   PresentVolts = Volts;
  
  //round and convert to integer
  int intVolts = (PresentVolts + 0.05) * 10;
  Tenths = intVolts % 10;
  Ones = (intVolts / 10) % 10;
  Tens = intVolts / 100;

  tft.setCursor(4, 4);

  if (Tens != OldTens) {
    tft.fillRect(0, 0, 20, 30, BLACK);
  }
  if (Ones != OldOnes) {
    tft.fillRect(21, 0, 20, 31, BLACK);
  }
  if (Tenths != OldTenths) {
    tft.fillRect(57, 0, 20, 31, BLACK);
  }
    tft.setTextColor(WHITE);
    tft.setTextSize(3);
    if(Volts<=9.9) {
      tft.print (" ");
      tft.print (Volts, 1);
    }
else if (Volts<=0.9) {
  tft.print (" 0");
      tft.print (Volts, 1);
}
    else{
      tft.print (Volts, 1);
    }
    
  OldTens = Tens;
  OldOnes = Ones;
  OldTenths = Tenths;
  Volts = Volts - .1;
  if (Volts < 0.0) {
    Volts = 15.0;
  }
  delay (500);

}