https://knowledge.keenfinity-group.com/intrusion-alarm-systems/article/how-to-correct-the-d1255-from-going-blank-when-add
How to Correct the D1255 from Going Blank when Adding or Modifying a User CMD 56
Issue While using Command 56 to enter/change passcodes, the screen goes blank after entering the user number and pressing enter. Solution The name ...