Cypress CY8CKIT-040 PSoC 4000 Pioneer Kit, Руководство пользователя

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CY8CKIT-040 PSoC
®
4000 Pioneer Kit Guide, Doc. # 001-91316 Rev. *F 85
Code Examples
Table 5-11. CapSense Component Parameters
Parameter Tab Present Value Rationale
Tuning method
General
Auto(SmartSense)
Automatically adjust sensitivity for different system
environments.
Threshold mode Automatic Enable run-time threshold calculation for 5:1 SNR.
Raw data noise
filter
First Order IIR 1/8
Filter out noise/unwanted spikes in raw count. This
setting can be tweaked based on requirement.
TouchPad0
Widgets Config
–
Add and configure the touchpad as shown in
Figure 5-42 .
ProximitySen-
sor0
–
Add and configure a proximity sensor as shown in
Figure 5-42 .
ProximitySen-
sor1
–
Add and configure a proximity sensor (Gang) as
shown in
Figure 5-42 . Note that this sensor is a
dummy sensor, which is ganged with the row ele-
ments of the touchpad for wakeup.
Analog switch
drive source
Advanced
PRS-Auto
For reduced EMI emission and enhanced EMC
immunity.
Sensor auto
reset
Disabled
Not required in the design. Can be added if
required by the application.
Low baseline
reset
5
System dependent number. Can be configured as
per the user needs.
Inactive sensor
connection
Ground
Make sure the proximity loop does not pick up any
charge when not scanned.
Shield Disabled Not used in the design.
Guard sensor Disabled Not used in the design.
Cmod pre-
charge Precharge by Vref
buffer
Vref is enough for precharging here, as there is
only one sensor, Cmod voltage will not drop too
low for a fast GPIO precharge.
Sensitivity
Scan Order
4
Select all the sensors by pressing and holding
[CTRL] or [Shift] and clicking on all the touchpad
sensors. When selected, enter the value in the
Sensitivity field.
1
Click ProximitySensor0 and set sensitivity as ‘1’
for maximum range.
5
Click ProximitySensor1 and set sensitivity as ‘5’
for minimum resolution of scan during sleep scan
for reduced power consumption.
Sensor ganging -
Gang the touchpad row elements to ProximitySen-
sor1 as shown in
Figure 5-43 .
Enable tuner
helper
Tuner Helper Disabled/unchecked No tuner used.