curTime = AbsoluteTime[];
curKey;
keyPressed = 0;
EventHandler["a", {"KeyDown" :> (
    If[keyPressed < 3,
      If[AbsoluteTime[] > .5 + curTime,
       Print[CurrentValue["EventKey"]];
       keyPressed++;
       ],
      If[AbsoluteTime[] > .1 + curTime,
       Print[CurrentValue["EventKey"]];
       keyPressed++;
       ]
      ]
     If[AbsoluteTime[] > 1 + curTime,
      curTime = AbsoluteTime[];
      curKey = CurrentValue["EventKey"];
      keyPressed = 0;
      ]
    )}
 ]

\!\(
TagBox["\<\"a\"\>",
EventHandlerTag[{"KeyDown" :> If[$CellContext`keyPressed < 3, 
If[AbsoluteTime[] > 0.5 + $CellContext`curTime, Print[
CurrentValue["EventKey"]]; Increment[$CellContext`keyPressed]; Null], 
If[AbsoluteTime[] > 0.1 + $CellContext`curTime, Print[
CurrentValue["EventKey"]]; Increment[$CellContext`keyPressed]; Null]]
        If[AbsoluteTime[] > 1 + $CellContext`curTime, \
$CellContext`curTime = AbsoluteTime[]; $CellContext`\
curKey = CurrentValue["EventKey"]; $CellContext`keyPressed = 0; Null],
      PassEventsDown -> Automatic, PassEventsUp -> True}]]\)

If[curKey == CurrentValue["key"] ,
 If[keyPressed < 5,
   If[AbsoluteTime[] > .5 + curTime,
    Print[CurrentValue["EventKey"]];
    keyPressed++;
    ],
   If[AbsoluteTime[] > .1 + curTime,
    Print[CurrentValue["EventKey"]];
    keyPressed++;
    ]
   ]
  If[AbsoluteTime[] > 1 + curTime,
   curTime = AbsoluteTime[];
   curKey = CurrentValue["EventKey"];
   keyPressed = 0;
   ]
 ]

i ;
n = 0;
run = True;
EventHandler["", {"KeyDown" :> (
    If[run,
     Print["set initial time"];
     i = AbsoluteTime[];
     run = False;,
     n++
     ];
    If[AbsoluteTime[] > 2 + i,
     Print[n];
     ]
    )}
 ]