UTFT clear screen

Projects Programming
1

Hello Guys,
I am using UTFT LIBRARY (UTFT - Rinky-Dink Electronics) for my project.
I am trying to display analog value from port A0 . The library only updates the screen when 'myGLCD.clrScr();' command is used.
I want to update the analog value as soon as the value changes without clearing the whole screen.
Request to get a solution for the same.
Here is the code:-

#include <UTFT.h>

// Declare which fonts we will be using
extern uint8_t SmallFont[];

UTFT myGLCD(ILI9225,11,13,10,8,9);

void setup()
{
randomSeed(analogRead(0));

// Setup the LCD
myGLCD.InitLCD();
myGLCD.setFont(SmallFont);
}

void loop()
{
int buf[218];
int x, x2;
int y, y2;
int r;

// Clear the screen and draw the frame

myGLCD.setColor(255, 0, 0);
myGLCD.fillRect(0, 0, 219, 13);
myGLCD.setColor(64, 64, 64);
myGLCD.fillRect(0, 162, 219, 175);
myGLCD.setColor(255, 255, 255);
myGLCD.setBackColor(255, 0, 0);
myGLCD.print("** Universal TFT Library **", CENTER, 1);
myGLCD.printNumI(analogRead(A0), CENTER, 15);
myGLCD.clrScr();
delay(5000);
}

2

Every time you read an analogue value, compare it to the last value you wrote to the screen.
If they're different, erase the portion of screen you wrote the value to, and write the new value.
Remember the new value.

Rinse and repeat.

Use code tags when posting code.

3

Hello,

Look at the UTFT manual, there are optional parameters for printNumI

4

Could you please tell me how to clean a particular portion of the screen in UTFT Library?@AWOL
N yeah printNumI doesn't have any option to clear or update a the data @guix

5

setColor and fillRect are the functions I'd try first

6

Tried that but not a good option, update is not fast. It is requiring specific code to clear a particular part.
The display update of the analogRead must be as fast as this (MQ5 Gas Sensor Raw Data From Arduino Uno - YouTube). Without clearing the whole screen.

7

I didn't mention clearing the whole screen, just the section you're going to write to.

8

yeah i understood for the specific portion of the screen and also i tried the same but just to update a value , these much line of code doesn't seem to be the solution.
Is there any other way?

9

You could print the old value in the background colour, then print the new value.

10

could you please give me a example code for the same.

11

No, sorry - I don't have that library here.

12

printNumI(num, x, y[, length[, filler]]);

Print an integer number at the specified coordinates.

You can use the literals LEFT, CENTER and RIGHT as the x-coordinate to align the string on the screen.

Parameters:

num: the value to print (-2,147,483,648 to 2,147,483,647) INTEGERS ONLY

x: x-coordinate of the upper, left corner of the first digit/sign

y: y-coordinate of the upper, left corner of the first digit/sign

length: minimum number of digits/characters (including sign) to display

filler: filler character to use to get the minimum length. The character will be inserted in front of the number, but after the sign. Default is ' ' (space).