When a capacitive sensing input pin is designated as a slider input, it will no longer function as a 'button' input and will not generate

button style touch/release events across the I2C buffer interface.

Touching the slider pads and moving a finger along a slider pad generates an event packet of type Slider, with the remaining two bytes

of the packet describing the calculated active position of the slider.

The range of possible reported slider active positions can be 0 to the maximum value of the slider as defined in the configuration profile,

which can be any value between 40 and 65534. The 65535 (0xFFFF) value is reserved for a slider untouched event.

Position 0 is always assigned to the lowest CSxx sensor enabled as a slider input. The maximum position value of the slider is assigned

to the highest CSxx sensor enabled as a slider input. All slider inputs in between are assumed to be routed to the slider contiguously,

lowest to highest.

Invalid

Configuration

Valid

Configuration

CS00

CS02

CS04

CS05

increasing slider

position

Valid

Configuration

CS03

CS02

CS01

CS00

increasing slider

position

CS00

CS02

CS01

CS03

Figure 4.6. Slider Behavior and Layout Constraints

Slider touch qualification uses the same touch deltas and thresholds that are defined in the configuration profile for all enabled sensors.

The user should configure slider sensors through the configuration profile, just as one would configure a sensor assigned to a capaci-

tive button.

For optimal performance, each sensor used in the slider should have roughly the same touch surface area dimensions.

If the touch-timeout feature is enabled, slider-assigned inputs will also be subject to being qualified as releases by the touch-timeout

feature.

The mutually exclusive button grouping feature does not affect slider-assigned sensors. Even if the mutually exclusive button grouping

feature is enabled, multiple slider-assigned sensors can still be used to resolve a finger's position on the slider.

4.5 Touch Time-Out

The touch time-out feature can be enabled and disabled through the configuration profile. When enabled, the device will monitor touch

event duration on each input independently.

When a touch event exceeds a duration specified in the configuration profile, the device forces a release event, even if the user is still

actively touching the sensor.

CPT112S Data Sheet

Functional Description

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