CTS Based Simple Bike Speedometer - Problem with CTS Pulse

Question

Everytime a magnet rotates, a sensor sends a CTS signal...I know the hardware works, as it works with another Speedometer writen with Delphi (Spinner on SourceForge). However, my program is getting the right speed, then numbers way too big for about three pulses, the right speed, garbage again, etc.... I'm assuming there is something about the CTS protocol and how the Java program needs to respond to a CTS event that I'm not getting. Or could it be my use of systemtime?
Here's code snippets.....
Oh, and I'm using DSR for cadence, and RI for heartrate, any similar issues that I need to be aware of using them?
Thanks
     serialPort = (SerialPort)portID.open("IntervalTrack", 0);
        serialPort.setSerialPortParams(9600,
                SerialPort.DATABITS_8,
                SerialPort.STOPBITS_1,
                SerialPort.PARITY_NONE);
        serialPort.addEventListener(this);
        serialPort.notifyOnDSR(true);
        serialPort.notifyOnCTS(true);
        serialPort.notifyOnCarrierDetect(true);
        serialPort.notifyOnRingIndicator(true);
        serialPort.notifyOnDataAvailable(true);
        serialPort.setDTR(false);
        serialPort.setRTS(true);--- snip ----
    public void serialEvent(SerialPortEvent e) {
            System.out.println(e.getEventType());
            switch (e.getEventType())
                case SerialPortEvent.CTS:
                    doCTS();
                    break;
                case SerialPortEvent.DSR:               
                    doDSR();
                    break;
                case SerialPortEvent.RI:
                    doRI();
                    break;
    private void doCTS(){
        double dblSpeedT2 = System.currentTimeMillis();
        double dblDeltaSpeedTime = dblSpeedT2 - this.dblSpeedT1;
       //todo resolve divide by zero  if (dblDeltaSpeedTime == 0.0)
        //                  dblDeltaSpeedTime = 1;
        this.dblSpeedKmPerHour = 3.6 * this.getWheelSizeInMM() /
                      dblDeltaSpeedTime;
        this.dblSpeedT1 = dblSpeedT2;
    }

Answer 1

Just for future reference if someone googles this unanswered question (so much for Java forums help.....).
The problem was that I needed to distinguish between the evt. changing from true to false and only computing for one or the other. So if it was false I computed, if it was true I continued. (err....or was it the other way around?) either way, thats the fix.....not sure on the why of this though..