Adding track markers from the DASH2 or DL1/DL2
To use a DASH2 button to add markers, refer to Programming soft buttons and programme one of the buttons to perform the “Add marker” function, as illustrated in Figure 4. To use a DL1/DL2 switch, connect a switch to the data logger as described in the documentation provided with the data logger itself.
When the data logger is in operation, a track marker will be added each time the DASH2 or logger button is pressed. When you wish to add track markers, it is advisable to drive slowly around the circuit and press the “add marker” button each time you pass a point you wish to use as a track marker. The first marker you add will ALWAYS be the LAP marker. The markers you subsequently add will split the track up into sectors. It should also be noted that each marker has an approach direction associated with it, as well as a position. This means that if you have a hairpin with the two straight-ways fairly close together and you added the track marker as you approach the hairpin, then both the approach and exit paths will cross the track marker, but the only time the software will log that you've crossed the track marker is when you have passed the marker in the same direction as it was added.
If the addition of a desired track marker was missed, it is possible to add a marker in after the first lap. The data logger will calculate where the track marker is in comparison to the track you have drawn so far, and if it is in between two other markers, the hardware will split the sector into two, but the track marker will be numbered as the next value.
When you press the button to add a track marker, a marker will be added at the next GPS sample point, so it could be up to 0.2 seconds before the marker is actually added (depending on the model and specification of data logger used). If you are travelling slowly when the markers are added this will have no serious side effects. If you are travelling quickly, it is unlikely that you will be able to position the track markers with great accuracy. This will not affect the timing between markers, as these are in the same place on every lap, but may affect the positioning of the markers with respect to circuit features.