Highchart function

//GLOBAL VARS TO MANAGE DATA
var TempTxR = [0,0]; //old_tx,new_tx
var TempRxR = [0,0]; //old_rx,new_rx
var FlagFirstTimeR = 0;
var interval = 5;
var window = 20;
///FUNCTION FOR RIGHT CHART
function requestDataRight() {
    $.ajax({
        url: 'cgi-bin/JSON_A.pl', //FUNCTION TO POPULATE RIGHT CHART
        success: function(point) {
            var series = charRight.series[0],
                shift = series.data.length > window; // shift if the series is longer than 20
            // dissect point
            var punto = eval(point);
            // Calculate difference between new and old points
            TempTxR[0] = TempTxR[1];
            TempTxR[1] = punto[1];
            TempRxR[0] = TempRxR[1];
            TempRxR[1] = punto[2];
            // Calculate delta
            var diff = (TempTxR[1] - TempTxR[0])/interval;
            var puntoSerieTx = [punto[0],diff];
            diff = (TempRxR[1] - TempRxR[0])/interval;
            var puntoSerieRx = [punto[0],diff];
            // Add the point
            if (FlagFirstTimeR == 0){
                FlagFirstTimeR = 1; //First point is off the scale =(
            }else{
                // add the point
                charRight.series[0].addPoint(puntoSerieTx, true, shift);
                charRight.series[1].addPoint(puntoSerieRx, true, shift);
            }
        },
        cache: false
    });
}