Can't print on LCD

Question

I'm a newbie here. And sorry for my bad English first of all.

Right now I'm working on VLC (Visible Light Communication). I have working code, in which output is displayed on the Serial Monitor. But now I want to print this output on an LCD.

I made necessary changes like including the LCD library and instead of Serial.print I used lcd.print. But nothing is displayed on the LCD.

Here is the modified code including LCD:

static int TRESHOLD = 500;
static unsigned int standardDelay = 13500000; //1350 is limit
// include the library code:
#include <LiquidCrystal.h>
// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 7,6,5,4);
void setup() {
 Serial.begin(9600); // 9600 bits per second
 pinMode(3,OUTPUT); //digital PWM 3 on output
 int sensorValue = 0;
 // set up the LCD's number of columns and rows:
 lcd.begin(16, 2);
 // initialize the serial communications:
}
void loop() {
 WriteChar('h');
 WriteChar('e');
 WriteChar('l');
 WriteChar('l');
 WriteChar('o');
 WriteChar('w');
 WriteChar('o');
 WriteChar('r');
 WriteChar('l');
 WriteChar('d');
}
void WriteChar(char str){
 switch (str - '0'){
 case 49:
 //code for a is 011 0001
 LightFlash(false, true, true, false, false, false, true);
 break;
 case 50:
 //code for b is 011 0010
 LightFlash(false, true, true, false, false, true, false);
 break;
 case 51:
 //code for c is 011 0011
 LightFlash(false, true, true, false, false, true, true);
 break;
 case 52:
 //code for d is 011 0100
 LightFlash(false, true, true, false, true, false, false);
 break;
 case 53:
 //code for e is 011 0101
 LightFlash(false, true, true, false, true, false, true);
 break;
 case 54:
 //code for f is 011 0110
 LightFlash(false, true, true, false, true, true, false);
 break;
 case 55:
 //code for g is 011 0111
 LightFlash(false, true, true, false, true, true, true);
 break;
 case 56:
 //code for h is 011 1000
 LightFlash(false, true, true, true, false, false, false);
 break;
 case 57:
 //code for i is 011 1001
 LightFlash(false, true, true, true, false, false, true);
 break;
 case 58:
 //code for j is 011 1010
 LightFlash(false, true, true, true, false, true, false);
 break;
 case 59:
 //code for k is 011 1011
 LightFlash(false, true, true, true, false, true, true);
 break;
 case 60:
 //code for l is 011 1100
 LightFlash(false, true, true, true, true, false, false);
 break;
 case 61:
 //code for m is 011 1101
 LightFlash(false, true, true, true, true, false, true);
 break;
 case 62:
 //code for n is 011 1110
 LightFlash(false, true, true, true, true, true, false);
 break;
 case 63:
 //code for o is 011 1111
 LightFlash(false, true, true, true, true, true, true);
 break;
 case 64:
 //code for p is 100 0000
 LightFlash(true, false, false, false, false, false, false);
 break;
 case 65:
 //code for q is 100 0001
 LightFlash(true, false, false, false, false, false, true);
 break;
 case 66:
 //code for r is 100 0010
 LightFlash(true, false, false, false, false, true, false);
 break;
 case 67:
 //code for s is 100 0011
 LightFlash(true, false, false, false, false, true, true);
 break;
 case 68:
 //code for t is 100 0100
 LightFlash(true, false, false, false, true, false, false);
 break;
 case 69:
 //code for u is 100 0101
 LightFlash(true, false, false, false, true, false, true);
 break;
 case 70:
 //code for v is 100 0110
 LightFlash(true, false, false, false, true, true, false);
 break;
 case 71:
 //code for w is 100 0111
 LightFlash(true, false, false, false, true, true, true);
 break;
 case 72:
 //code for x is 100 1000
 LightFlash(true, false, false, true, false, false, false);
 break;
 case 73:
 //code for y is 100 1001
 LightFlash(true, false, false, true, false, false, true);
 break;
 case 74:
 //code for z is 100 1010
 LightFlash(true, false, false, true, false, true, false);
 break;
 default:
 lcd.print(str - '0');
 lcd.print("CAME IN DEFAULT IN WRITECHAR");
 break;
 }
}
void LightFlash(boolean a, boolean b, boolean c, boolean d, boolean e, boolean f, boolean g){
 digitalWrite(3,LOW);
 if (a == true){
 digitalWrite(3,HIGH);
 }
 delayMicroseconds(standardDelay/2);
 boolean sensorValue1 = (analogRead(A0)>TRESHOLD);
 delayMicroseconds(standardDelay/2);
 digitalWrite(3,LOW);
 if (b == true){
 digitalWrite(3,HIGH);
 }
 delayMicroseconds(standardDelay/2);
 boolean sensorValue2 = (analogRead(A0)>TRESHOLD);
 delayMicroseconds(standardDelay/2);
 digitalWrite(3,LOW);
 if (c == true){
 digitalWrite(3,HIGH);
 }
 delayMicroseconds(standardDelay/2);
 boolean sensorValue3 = (analogRead(A0)>TRESHOLD);
 delayMicroseconds(standardDelay/2);
 digitalWrite(3,LOW);
 if (d == true){
 digitalWrite(3,HIGH);
 }
 delayMicroseconds(standardDelay/2);
 boolean sensorValue4 = (analogRead(A0)>TRESHOLD);
 delayMicroseconds(standardDelay/2);
 digitalWrite(3,LOW);
 if (e == true){
 digitalWrite(3,HIGH);
 }
 delayMicroseconds(standardDelay/2);
 boolean sensorValue5 = (analogRead(A0)>TRESHOLD);
 delayMicroseconds(standardDelay/2);
 digitalWrite(3,LOW);
 if (f == true){
 digitalWrite(3,HIGH);
 }
 delayMicroseconds(standardDelay/2);
 boolean sensorValue6 = (analogRead(A0)>TRESHOLD);
 delayMicroseconds(standardDelay/2);
 digitalWrite(3,LOW);
 if (g == true){
 digitalWrite(3,HIGH);
 }
 delayMicroseconds(standardDelay/2);
 boolean sensorValue7 = (analogRead(A0)>TRESHOLD);
 delayMicroseconds(standardDelay/2);
 delayMicroseconds(3*standardDelay); //1 second passed
 long result = 0;
 result = 1000000*sensorValue1 + 100000*sensorValue2 + 10000*sensorValue3
 + 1000*sensorValue4 + 100*sensorValue5 + 10*sensorValue6 + 1*sensorValue7;
 //lcd.print(result);
 PrintChar(result);
}
void PrintChar(long binary){
 switch (binary){
 case 110001:
 //code for a is 011 0001 
 lcd.write("a");
 break;
 case 110010:
 //code for b is 011 0010 
 lcd.print("b");
 break;
 case 110011:
 //code for c is 011 0011 
 lcd.print("c");
 break;
 case 110100:
 //code for d is 011 0100 
 lcd.print("d");
 break;
 case 110101:
 //code for e is 011 0101
 lcd.print("e");
 break;
 case 110110:
 //code for f is 011 0110
 lcd.print("f");
 break;
 case 110111:
 //code for g is 011 0111
 lcd.print("g");
 break;
 case 111000:
 //code for h is 011 1000
 lcd.print("h");
 break;
 case 111001:
 //code for i is 011 1001
 lcd.print("i");
 break;
 case 111010:
 //code for j is 011 1010
 lcd.print("j");
 break;
 case 111011:
 //code for k is 011 1011
 lcd.print("k");
 break;
 case 111100:
 //code for l is 011 1100
 lcd.print("l");
 break;
 case 111101:
 //code for m is 011 1101
 lcd.print("m");
 break;
 case 111110:
 //code for n is 011 1110
 lcd.print("n");
 break;
 case 111111:
 //code for o is 011 1111
 lcd.print("o");
 break;
 case 1000000:
 //code for p is 100 0000
 lcd.print("p");
 break;
 case 1000001:
 //code for q is 100 0001
 lcd.print("q");
 break;
 case 1000010:
 //code for r is 100 0010
 lcd.print("r");
 break;
 case 1000011:
 //code for s is 100 0011
 lcd.print("s");
 break;
 case 1000100:
 //code for t is 100 0100
 lcd.print("t");
 break;
 case 1000101:
 //code for u is 100 0101
 lcd.print("u");
 break;
 case 1000110:
 //code for v is 100 0110
 lcd.print("v");
 break;
 case 1000111:
 //code for w is 100 0111
 lcd.print("w");
 break;
 case 1001000:
 //code for x is 100 1000
 lcd.print("x");
 break;
 case 1001001:
 //code for y is 100 1001
 lcd.print("y");
 break;
 case 1001010:
 //code for z is 100 1010
 lcd.print("z");
 break;
 case 11000:
 lcd.print("dit gebeurt vaak");
 break;
 case 1011001:
 lcd.print("dit ook");
 break;
 case 100001:
 lcd.print("tenslotte dit nog");
 break;
 case 1011000:
 lcd.print("en dit is de laatste denk ik");
 break;
 default:
 lcd.print(binary);
 lcd.print("CAME IN DEFAULT ON PRINTCHAR");
 break;
 }
}

I want to print this output on LCD. But I'm not able to do that. Please help me out.

Circuits:

(1) VLC Circuit

VLC Circuit

(2) LCD Circuit

LCD Circuit

I combined both circuits above and made a final circuit.

The VLC circuit is set up in which DATA is transmitted from SIMPLE LED and Capture on PHOTODIODE. And using LCD Circuit I want to display data on LCD.

• Michel Keijzers: I don't see any code related to the LCD.
• PRATIK I PANCHAL: @MichelKeijzers Becuase I remove it and upload original code. Already I mention that thing. Just check it out above the code. Ok...
• user31481: Not enough information. Post your LCD code and schematics.
• PRATIK I PANCHAL: @LookAlterno Ok, let me.
• Jot: Connecting a LCD display to an Arduino is not easy because of all those wires and the contrast and the cheap displays need enough voltage (above 4.5 V). I had some trouble with it myself. The second time it was a piece of cake. Forget your project for a moment and make a sketch that only uses the LCD. Start here: arduino.cc/en/Reference/LiquidCrystal

Answer 1

There is so many problems with your code. It can be so much short.

Take WriteChar. Why mess with binary value for chars? Use char directly, just here:

void setup() {
 Serial.begin(9600);
 WriteChar('h');
 WriteChar('e');
}
void loop() {
}
void WriteChar(char c) {
 boolean b7 = c & B1000000;
 boolean b6 = c & B0100000;
 boolean b5 = c & B0010000;
 boolean b4 = c & B0001000;
 boolean b3 = c & B0000100;
 boolean b2 = c & B0000010;
 boolean b1 = c & B0000001;
 Serial.println(c);
 LightFlash(b7, b6, b5, b4, b3, b2, b1);
}
void LightFlash(boolean b7, boolean b6, boolean b5, boolean b4, boolean b3, boolean b2, boolean b1) {
 Serial.print(b7 ? "1" : "0"); 
 Serial.print(b6 ? "1" : "0"); 
 Serial.print(b5 ? "1" : "0"); 
 Serial.print(b4 ? "1" : "0"); 
 Serial.print(b3 ? "1" : "0"); 
 Serial.print(b2 ? "1" : "0"); 
 Serial.println(b1 ? "1" : "0"); 
}

There is more simply ways to write that (using arrays and loops) but this is easier to understand. And better, pass the char directly to LightBlash.

Don't use a string when you just pass a char to a function.

Answer 2

Finally, got the problem. My code is working fine. I have a problem with my LCD connection.

I write

LiquidCrystal lcd(12, 11, 7, 6, 5, 4);

Instead of

LiquidCrystal lcd(12, 11, 4, 5, 6, 7);