     mma.setLowNoiseMode(true);
     mma.setPowerMode(MMA_HIGH_RESOLUTION);
 
+    mma.setHighPassFilter(true); // Defaults (?) to highest cutoff: 16Hz
+
     // data ready interrupt
     mma.setInterruptsEnabled(MMA_DATA_READY);
     // all defaults to INT2

    lastAccTime = newAccTime;
    lastAccValue = x;

    Bluetooth.print(xVelocity);
    Bluetooth.println(x);
    
    //if (abs(x) > 0.05) {
    //    Serial.println(x);

void setupBluetooth() {
    Bluetooth.begin(BluetoothSerialSpeed);
    Bluetooth.println("DBluetooth module active.");
}

void calibrateZeroVel() {

}

float trapezoidalRule(float fa, float fb, int dt) {
