glitchy lcd graphics

Other Hardware Displays
1

i recently got a little 1.8inch lcd tft working and it has some randomly colored pixels around the boarder when i send it data i have resistors in line with all the data pin (red black black gold (brown body)) and i am wondering if the resistors are too low or two high if they are too low i dont want ti remove them and if they are too high i want to buy new ones...here is the lcd eBay im using a arduino nano

2

brenden_nerd_:
i recently got a little 1.8inch lcd tft working and it has some randomly colored pixels around the boarder when i send it data i have resistors in line with all the data pin (red black black gold (brown body)) and i am wondering if the resistors are too low or two high if they are too low i dont want ti remove them and if they are too high i want to buy new ones...here is the lcd http://pages.ebay.com/link/?nav=item.view&id=191828925767&alt=web im using a arduino nano

Would you please post a code and a schematic of your set up? It is hard to judge without them.
It would sound silly, but I would check your connections 1 more time.Also, are you sure that your connections are correct and code is good?

3

ok the glithc is at the bottom of the screen and on the left side... i have every connection on the screen with one of the resistors i described before, the one thing i do not have connected is the back light (bl) ... vcc is connected to 3.3v gnd is connected to ground scl is connected to d13 sda to d11 res to pin9 dc to pin8 cs to pin10 ...here is the code

/*
  Arduino TFT text example

  This example demonstrates how to draw text on the
  TFT with an Arduino. The Arduino reads the value
  of an analog sensor attached to pin A0, and writes
  the value to the LCD screen, updating every
  quarter second.

  This example code is in the public domain

  Created 15 April 2013 by Scott Fitzgerald

  http://www.arduino.cc/en/Tutorial/TFTDisplayText

 */

#include <TFT.h>  // Arduino LCD library
#include <SPI.h>

// pin definition for the Uno
#define cs   10
#define dc   8
#define rst  9

// pin definition for the Leonardo
// #define cs   7
// #define dc   0
// #define rst  1

// create an instance of the library
TFT TFTscreen = TFT(cs, dc, rst);

// char array to print to the screen
char sensorPrintout[4];

void setup() {

  // Put this line at the beginning of every sketch that uses the GLCD:
  TFTscreen.begin();

  // clear the screen with a black background
  TFTscreen.background(0, 0, 0);

  // write the static text to the screen
  // set the font color to white
  TFTscreen.stroke(255, 255, 255);
  // set the font size
  TFTscreen.setTextSize(2);
  // write the text to the top left corner of the screen
  TFTscreen.text("Sensor Value :\n ", 0, 0);
  // ste the font size very large for the loop
  TFTscreen.setTextSize(5);
}

void loop() {

  // Read the value of the sensor on A0
  String sensorVal = String(analogRead(A0));

  // convert the reading to a char array
  sensorVal.toCharArray(sensorPrintout, 4);

  // set the font color
  TFTscreen.stroke(255, 255, 255);
  // print the sensor value
  TFTscreen.text(sensorPrintout, 0, 20);
  // wait for a moment
  delay(250);
  // erase the text you just wrote
  TFTscreen.stroke(0, 0, 0);
  TFTscreen.text(sensorPrintout, 0, 20);
}
4

So has no one had this problem or what??

5

The display you have has a row and column offset that is different to the standard library setup.

Try the library here, it is compatible with the Adafruit/TFT library and has the offset compensation added.