Problem displaying time from DS3231 on tft.


Im trying to creata a digital klock displayd on a tft display. Im using DS3231 as klock,

The klock works just fine when i print it on seral.monitor, but when i conect the tft nothing displays there. Just backlight and no more,

When i put // before all comands fore the DS3231 and put som random text to be displayd it all works. So im prety sure the code fore the display is fine.
Is there som interferance betwean the klock and display?

#include <Adafruit_GFX.h> // Hardware-specific library
#include <MCUFRIEND_kbv.h>

MCUFRIEND_kbv tft;
DS3231  rtc(SDA, SCL);

#define BLACK    0x0000
#define BLUE     0x001F
#define RED      0xF800
#define GREEN    0x07E0
#define CYAN     0x07FF
#define MAGENTA  0xF81F
#define YELLOW   0xFFE0
#define WHITE    0xFFFF

void setup()



  uint16_t identifier = tft.readID();
  Serial.print("ID = 0x");
  Serial.println(identifier, HEX);
  if (identifier == 0xEFEF) identifier = 0x9486;

  rtc.setTime(22, 36, 0);     // Set the time to 12:00:00 (24hr format)


void loop()

  tft.setTextColor(GREEN, BLACK);
  tft.setCursor(10, 10);


  delay (1000);


Mcufriend Uno Shields use A4 for LCD_RST.

A4 is SDA on a Uno. This means that you can not use I2C on a Uno with the TFT Shield.

Either change to a different Arduino or make a hardware modification to the TFT Shield. (please say which controller you have)


O sorry :-[ I use a normal UNO.

I have conected it as you see in te picture.

Yes, the DS3231 will work fine with the TFT removed. Just report the time and date to the Serial Terminal.

Sorry for my bad english, maby im not able to explain my problem.

Yes it works just fine when tft ir removed. But what i try to buld is a klock displayd on the tft.

If i understand you correct, its not posible to run it this way?
whit the DS3231 attached this way and then just add the tft sheld?