16 X 2 LCD display blank with Arduino Uno So I am following this tutorial to make my arduino display hello world and millis(), I got it to work for a minute, but then it stopped updating the milliseconds, and when I pushed the reset button it went blank. since then, It has been blank but I have double, triple, and qaudruple checked checked my wiring, and it is flawless. I tried it with both of my 16 segment displays, but to no avail. I have redone the wiring, but it is still blank. Does anybody know what I could be doing wrong? 

I followed this diagram 
this is my code:

// include the library code:
#include &lt;LiquidCrystal.h&gt;

// initialize the library by associating any needed LCD interface pin
// with the arduino pin number it is connected to
const int rs = 12, en = 11, d4 = 5, d5 = 4, d6 = 3, d7 = 2;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7); 

void setup() {
  // set up the LCD's number of columns and rows:
  lcd.begin(16, 2);
  // Print a message to the LCD.
  lcd.print("hello, world!");
}

void loop() {
  // set the cursor to column 0, line 1
  // (note: line 1 is the second row, since counting begins with 0):
  lcd.setCursor(0, 1);
  // print the number of seconds since reset:
  lcd.print(millis() / 1000);
}


This is the result (the screen is lit up, but there is no text even when turning the potentiometer)
It is most likely that I wasn't providing enough power to the arduino, and or had the potentiometer set to the wrong point. according to this post, you shouldn't run the arduino and display off of USB, because it may not actually be providing 5 volts. So I plugged it into the wall using a DC adapter. It now works.