How to insert black box character in lcd?

Projects Programming
1

Hello, I would like to know how to insert black box character in LCD. I know that it's lcd.print(char(255)); but I need to know hoe to insert it for several positions below set.Cursor(8,0); int that particular case there would be 8 black boxes. Experience is: I am taking mesurement with potentiometer and instead of reading value of potentiometer, I read black boxes from (0 to 16)

2

If you mean a bar graph, look here: Arduino Playground - LcdBarGraph Library
Or just google "arduino lcd bar graph" or "arduino lcd custom characters"

3

Thank's!

4

My code is not working properly if I want to use first line of LCD. It shows bars graph on the first and second lines of LCD. I have to comment this part to display the graph on the second line:

// drawing black rectangles on LCD
//if(b>=1) { 
//  for(int i=1;1<b;i++){
//    lcd.print(char(255));
//    c=i;
//  }
//  b=b-c;
//}

My code:

#include <LiquidCrystal.h>
#define longueur1 16.0
#define longueur2 16.1

float percent1;
float percent2;

unsigned char c;
unsigned char d;

LiquidCrystal lcd(8, 9, 4, 5, 6, 7);

void setup() {
delay(100);
lcd.begin(16, 2);
}

void loop()
{

lcd.setCursor(0, 0);

//ADC conversion
unsigned int Potant1 = analogRead(A12);
unsigned int Potant2 = analogRead(A15);

percent1 = Potant1/1024.0*100.0;
lcd.setCursor(0,0);
float b=longueur1/100*percent1;

// drawing black rectangles on LCD
//if(b>=1) { 
//  for(int i=1;1<b;i++){
//    lcd.print(char(255));
//    c=i;
//  }
//  b=b-c;
//}

percent2 = Potant2/1024.0*100.0;
lcd.setCursor(0,1);
float a=longueur2/100*percent2;

// drawing black rectangles on LCD
if (a>=1) {
for (int i=1;i<a;i++){
lcd.print(char(255));
d=i;
}
a=a-d;
}

//efface la ligne
for (int i =0;i<(longueur1-d);i++) {
lcd.print(" ");
}

for (int i =0;i<(longueur2-c);i++) {
lcd.print(" ");
}



delay(500);
}
5

Typo which will fill entire lcd memory with black boxes and wrap to second line.

for(int i=1;1<b;i++)

should be

for(int i=1;i<b;i++)