30
Atmel AVR8015
32185A-AVR-01/12
Modify all global and sensor parameters runtime as shown in
.
Detect threshold.
1. Open the Kit/Sensor Configuration window, select any sensor and change the
values of the detect threshold. Click on Write to kit.
2. Observe how sensitivity of that sensor changes with different values.
3. The lower the value, the more sensitive is the sensor.
A sensor’s detect threshold defines how much its signal must drop below its
reference level to qualify as a potential touch detect. It has a range of between 3
and 255.
For more details on all the configuration parameters, please refer to the
Atmel QTouch Library User Guide.
Maximum ON duration.
1. Click on the View Menu and click on Graph View. The QTouch Graph view
window opens.
2. Select data set for channel 7 and observe what happens on touch.
Figure 4-29.
Maximum ON duration = 0.
3. If a touch happens for a prolonged duration when the Maximum ON duration is
zero, the sensor remains in detect.
4. Open the Kit/Sensor configuration window.
5. Change the Maximum ON duration to 30 and the sensor automatically
recalibrates after six seconds.
Figure 4-30.
Maximum ON duration = 30.
If an object unintentionally contacts a sensor and results in touch detection for a
prolonged interval, it is usually desirable to recalibrate the sensor in order to
restore its function, perhaps after a time delay of some seconds. The Maximum
ON duration timer monitors such detections.
