Using Serial input together with SPI

Question

I am working on a project where I am receiving serial data on UART6_RX. This works perfectly fine.

However, when I add a touchscreen button to the screen and in the main while loop check if it is touched, the UART_RX doesn't receive any data anymore. I've got the feeling that it has something to do with interrupts.

I currently have the following code:

int main()
{
    device.baud(31250);  
    lcd.Clear(BACK_COLOR);

    Button firstButton(lcd, ts, 10, Y0, btnWidth, btnHeight,LCD_COLOR_RED, BACK_COLOR, "My First Button", Font24);

    while(1) {  

        if (firstButton.Touched()) //If I remove this if statement, everything works perfectly. 
        {
            int n = 10; 
        }      
       // __disable_irq(); //Tried this, but without succes

        if (device.readable()) {
            char cReceivedByte = device.getc();
            unsigned long result= doSomethingAmazing(cOntvangenByte);
            char buf[10];
            sprintf(buf, "%05lu\r\n", result);

            lcd.SetBackColor(LCD_COLOR_GREEN);
            lcd.SetTextColor(LCD_COLOR_WHITE);
            lcd.SetFont(&Font24);
            lcd.DisplayStringAt(270, LINE(5), (uint8_t *)buf, LEFT_MODE);
        }
      //  __enable_irq();
    }
}

I using the ARM - mbed compiler and am running it on the following dev board: - STM32F7-Discovery

Who knows what is going on and how I can solve it?

Thanks a million times,

Alex