Datasheet

CY8C20xx6A/H CapSense Design Guide Doc. No. 001-65973 Rev. *A 18
3.3.3 Difference Count
The difference count is the difference between the raw count and the baseline of the sensor. Usually, the difference
count is zero when the sensor is inactive. When the sensor is touched, it causes the raw count to increase, and
results in a positive difference count value.
Baseline values are stored in an integer array named UMname_waSnsDiff[] where UMname is CSD, SmartSense, or
CSA_EMC.
3.3.4 Sensor State
The state of each sensor is represented as 1 if the button is ON and 0 if the button is OFF.
The ON/OFF states for all of the sensors are stored in a byte array named UMname_baSnsOnMask[ ] where
UMname is CSD, SmartSense, or CSA_EMC. Each array element can hold the ON/OFF state of eight sensors.
UMname_baSnsOnMask[0] contains the masked bits for sensors 0 through 7. UMname_baSnsOnMask[1] contains
the masked bits for sensors 8 through 15. This byte array contains as many elements as are necessary to include all
of the sensors.
If any sensor is ON, the bIsAnySensorActive() function returns a 1. If all sensors are OFF, the bIsAnySensorActive()
function returns a 0.
3.4 High-Level Parameters
Figure 3-5. High Level Parameters
      + ,   =      
       ,   =  Equation 4
Where:
Sample Count = the number of samples measured above Finger Threshold + Hysteresis
3.4.1 Finger Threshold
The finger threshold parameter defines the sensitivity of the sensor to finger touches. It is used in conjunction with the
Hysteresis parameter to determine the sensor state, as defined in Equation 4.
For individual sensors (not contained in a slider group) the Finger Threshold parameter is stored in a byte array
named. baBtnFThreshold[] that contains as many elements as are necessary to include all sensors.