In your Control Panel, double click on "Capacitive Scroll Sensor":

Before you open a Phidget channel in your program, you can set these properties to specify which channel to open. You can find this information through the Control Panel.

1. Open the Control Panel and double-click on the red map pin icon:

2. The Addressing Information window will open. Here you will find all the information you need to address your Phidget in your program.

See the Phidget22 API for your language to determine exact syntax for each property.

Unlike most other Phidgets, setting a data interval on the HIN1001 affects its initial “wake up” time, instead of the overall data rate. After the first touch has been detected, the device will stream data as fast as possible (up to every 16ms, as data becomes available).

This means that if setting a data interval of 250ms, the first touch may need to be held up to 250ms to wake the device, after which subsequent touches on all channels will be detected much faster, until no touch is detected for a few seconds. Once the device has been left alone for a few seconds, it will resume its low-power state and wait for the next touch.

The capacitive touch sensors rely on checking capacitance against a threshold to detect when they are touched. As a result you need to keep a good baseline of the capacitance of the sensor's environment. The HIN1001 will recalibrate its baseline levels if it detects a constant touch for more than 50 seconds, in order to prevent getting stuck in a touched state. Similarly, it will recalibrate its baseline capacitance to adjust to falling capacitance (such as when it is moved away from a surface) in order to prevent getting stuck in a not-touched state. The latter adjustment happens as soon as the baseline is detected to have fallen.

Since the touch wheel is circular, calculating the change in position of a finger over the wheel can be more involved than simply subtracting one position from another. In cases where the value crosses the zero point, a simple subtraction would indicate a large movement in the opposite direction. For example a movement from 0.9 to 0.1 would appear as a movement of -0.8, when a movement of +0.2 is much more likely. As such, a change in position should be calculated taking this into account. Here is an example of how to do the calculation in C:

static void CCONV
onTouchHandler(PhidgetCapacitiveTouchHandle ch, void *ctx, double touchValue) {			

   double change = (touchValue - oldPos);  
   static double oldPos;

   if (change > 0.5)
      change -= 1;
   else if (change < -0.5)
      change += 1;

   oldPos = touchValue;

   ...
}