4.6.2 Buzzer Configuration

When enabled, buzzer output will appear on the CS11/buzzer pin (pin 10) of the device. When buzzer output is enabled, CS11 is not

available for capactive input sensing.

When activated, the buzzer will remain active for either the duration specified in the configuration profile, or until the last active sensor

has qualified a touch release.

The configuration profile supports configuration of output frequencies ranging from 1 kHz to 4 kHz.

The configuration profile can configure the buzzer output pin to either push pull mode or open drain mode.

4.7 Mutually Exclusive Buttons

When enabled through the configuration profile, this system allows one and only one capacitive sensing input to be qualified as active

at a time. The first sensor active will remain the only sensor active until released. The device will internally qualify multiple touch and

release events but will not report them.

If multiple sensors have been internally qualified as active, the first sensor's touch event will be reported. If a touch event occurs simul-

taneously on more than one sensor, the touch with the highest touch delta will be reported.

If two sensors are qualified as active and the sensor being reported as active qualifies a touch release, the device will report that re-

lease and then report a touch qualification on the still-active second sensor.

In the case where a device has simultaneously qualified more than two active sensors and the reported active sensor qualifies and

reports a release, the remaining qualified sensor with the highest sensor name will then be reported. For example, if sensors CS00,

CS01, and CS02 are active with CS00 externally reported as active, after CS00's release, CS02 would be externally reported as an

active sensor unless the device has already qualified a touch release on CS02.

If both the touch timeout feature and the mutually exclusive button group feature are enabled, the timeout timer will only run on the

touch that is externally reported as being active.

Device Execution

physical touch on pad

touch reported by CPT device

release reported by CPT device

Figure 4.9. Mutually-Exclusive Button Operation

CPT112S Data Sheet

Functional Description

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