PSoC™ 4: CAPSENSE™ CSX button tuning

This code example demonstrates how to manually tune a mutual capacitance (CSX)-based button widget in PSoC™ 4 devices using the CAPSENSE™ tuner GUI.

This document includes:

A high-level overview of the CAPSENSE™ CSX widget tuning flow.
An example to manually tune a CSX button widget.
A procedure on how to use the CAPSENSE™ tuner to monitor the CAPSENSE™ raw data and fine-tune the CSX button for optimum performance such as reliability, power consumption, and response time.

View this README on GitHub.

Provide feedback on this code example.

Requirements

ModusToolbox™ software v3.1 or later (tested with v3.1)

Note: This code example version requires ModusToolbox™ software version 3.0 or later and is not backward compatible with v2.4 or older versions.
Board support package (BSP) minimum required version: 3.0.0
Programming language: C
Associated parts: PSoC™ 4000S, PSoC™ 4100S, PSoC™ 4100S Plus and PSoC™ 4500S

Supported toolchains (make variable 'TOOLCHAIN')

GNU Arm® embedded compiler v11.3.1 (GCC_ARM) - Default value of TOOLCHAIN
Arm® compiler v6.16 (ARM)
IAR C/C++ compiler v9.30.1 (IAR)

Supported kits (make variable 'TARGET')

PSoC™ 4100S Plus prototyping kit (CY8CKIT-149) - Default value of TARGET
PSoC™ 4100S CAPSENSE™ pioneer kit (CY8CKIT-041-41XX)
PSoC™ 4000S CAPSENSE™ prototyping kit (CY8CKIT-145-40XX)
PSoC™ 4500S pioneer kit (CY8CKIT-045S)

Hardware setup

This example uses the board's default configuration. See the kit user guide to ensure that the board is configured correctly.

Note: The PSoC™ 4 kits ship with KitProg2 installed. The ModusToolbox™ software requires KitProg3. Before using this code example, make sure that the board is upgraded to KitProg3. The tool and instructions are available in the Firmware Loader GitHub repository. If you do not upgrade, you will see an error like "unable to find CMSIS-DAP device" or "KitProg firmware is out of date".

Software setup

This example requires no additional software or tools.

Using the code example

Create the project and open it using one of the following:

In Eclipse IDE for ModusToolbox™ software

Click the New Application link in the Quick Panel (or, use File > New > ModusToolbox™ Application). This launches the Project Creator tool.
Pick a kit supported by the code example from the list shown in the Project Creator - Choose Board Support Package (BSP) dialog.

When you select a supported kit, the example is reconfigured automatically to work with the kit. To work with a different supported kit later, use the Library Manager to choose the BSP for the supported kit. You can use the Library Manager to select or update the BSP and firmware libraries used in this application. To access the Library Manager, click the link from the Quick Panel.

You can also just start the application creation process again and select a different kit.

If you want to use the application for a kit not listed here, you may need to update the source files. If the kit does not have the required resources, the application may not work.
In the Project Creator - Select Application dialog, choose the example by enabling the checkbox.
(Optional) Change the suggested New Application Name.
The Application(s) Root Path defaults to the Eclipse workspace which is usually the desired location for the application. If you want to store the application in a different location, you can change the Application(s) Root Path value. Applications that share libraries should be in the same root path.
Click Create to complete the application creation process.

For more details, see the Eclipse IDE for ModusToolbox™ software user guide (locally available at {ModusToolbox™ software install directory}/docs_{version}/mt_ide_user_guide.pdf).

In command-line interface (CLI)

ModusToolbox™ software provides the Project Creator as both a GUI tool and the command line tool, "project-creator-cli". The CLI tool can be used to create applications from a CLI terminal or from within batch files or shell scripts. This tool is available in the {ModusToolbox™ software install directory}/tools_{version}/project-creator/ directory.

Use a CLI terminal to invoke the "project-creator-cli" tool. On Windows, use the command line "modus-shell" program provided in the ModusToolbox™ software installation instead of a standard Windows command-line application. This shell provides access to all ModusToolbox™ software tools. You can access it by typing modus-shell in the search box in the Windows menu. In Linux and macOS, you can use any terminal application.

The "project-creator-cli" tool has the following arguments:

Argument	Description	Required/optional
`--board-id`	Defined in the `<id>` field of the BSP manifest	Required
`--app-id`	Defined in the `<id>` field of the CE manifest	Required
`--target-dir`	Specify the directory in which the application is to be created if you prefer not to use the default current working directory	Optional
`--user-app-name`	Specify the name of the application if you prefer to have a name other than the example's default name	Optional

The following example clones the "CAPSENSE™ CSX button tuning" application with the desired name "CSXButtonTuning" configured for the CY8CKIT-041-41XX BSP into the specified working directory, C:/mtb_projects:

project-creator-cli --board-id CY8CKIT-041-41XX --app-id mtb-example-psoc4-capsense-csx-button-tuning --user-app-name CSXButtonTuning --target-dir "C:/mtb_projects"

Note: The project-creator-cli tool uses the git clone and make getlibs commands to fetch the repository and import the required libraries. For details, see the "Project creator tools" section of the ModusToolbox™ software user guide (locally available at {ModusToolbox™ software install directory}/docs_{version}/mtb_user_guide.pdf).

To work with a different supported kit later, use the Library Manager to choose the BSP for the supported kit. You can invoke the Library Manager GUI tool from the terminal using make library-manager command or use the Library Manager CLI tool "library-manager-cli" to change the BSP.

The "library-manager-cli" tool has the following arguments:

Argument	Description	Required/optional
`--add-bsp-name`	Name of the BSP that should be added to the application	Required
`--set-active-bsp`	Name of the BSP that should be as active BSP for the application	Required
`--add-bsp-version`	Specify the version of the BSP that should be added to the application if you do not wish to use the latest from manifest	Optional
`--add-bsp-location`	Specify the location of the BSP (local/shared) if you prefer to add the BSP in a shared path	Optional

Following example adds the CY8CKIT-149 BSP to the already created application and makes it the active BSP for the app:

~/ModusToolbox/tools_3.1/library-manager/library-manager-cli --project "C:/mtb_projects/CSXButtonTuning" --add-bsp-name CY8CKIT-149 --add-bsp-version "latest-v3.X" --add-bsp-location "local"

~/ModusToolbox/tools_3.1/library-manager/library-manager-cli --project "C:/mtb_projects/CSXButtonTuning" --set-active-bsp APP_CY8CKIT-149

In third-party IDEs

Use one of the following options:

Use the standalone Project Creator tool:
1. Launch Project Creator from the Windows Start menu or from {ModusToolbox™ software install directory}/tools_{version}/project-creator/project-creator.exe.
2. In the initial Choose Board Support Package screen, select the BSP, and click Next.
3. In the Select Application screen, select the appropriate IDE from the Target IDE drop-down menu.
4. Click Create and follow the instructions printed in the bottom pane to import or open the exported project in the respective IDE.

Use command-line interface (CLI):
1. Follow the instructions from the In command-line interface (CLI) section to create the application.
2. Export the application to a supported IDE using the make <ide> command.
3. Follow the instructions displayed in the terminal to create or import the application as an IDE project.

For a list of supported IDEs and more details, see the "Exporting to IDEs" section of the ModusToolbox™ software user guide (locally available at {ModusToolbox™ software install directory}/docs_{version}/mtb_user_guide.pdf).

Tuning flow summary

Figure 1 gives a high-level summary on how to tune a CSX-based CAPSENSE™ button in PSoC™ 4 devices. See the “Manual tuning” section in AN85951 – PSoC™ 4 and PSoC™ 6 MCU CAPSENSE™ design guide for information on the hardware and threshold parameters that determines the CAPSENSE™ touch performance.

Figure 1. High-level overview of CSX button tuning

Operation

This process involves the following stages:

Stage 1: Set initial hardware parameters

Connect the board to your PC using the provided micro USB cable through the KitProg3 USB connector.
Launch the CAPSENSE™ Configurator. See the "Launch the CAPSENSE™ configurator" section from the ModusToolbox™ CAPSENSE™ configurator guide.
In the Basics tab, you will find a single widget Button0 configured as a CSX button.
Navigate to the Advanced tab and select the General sub tab. Leave all the filter parameters at their default settings. Filters will be enabled depending on the SNR and system time requirements.

Select the Enable self-test library checkbox to perform sensor capacitance measurement as explained in the Calculate the maximum Tx clock frequency section.

Figure 2. CAPSENSE™ Configurator - General settings

Click the Advanced tab and then select the CSX Settings sub tab. Configure the parameters as shown in Table 1 and Figure 3.

Table 1. Advanced tab - CSX Settings

Parameter	Value	Remarks
Modulator clock divider	1 (to obtain the maximum allowed by the selected device)	A higher modulator clock frequency reduces flat-spots and increases measurement's accuracy and sensitivity. It is therefore recommended to select the highest possible available modulator clock frequency.
Inactive electrode connection	Ground	Inactive sensors are connected to ground to provide good shielding from noise sources.
Enable IDAC auto-calibration	Checked	Enabling auto-calibration allows the device to automatically choose the optimal IDAC calibration point (for CSX, this is 40 percent of the maximum value).

Figure 3. CAPSENSE™ Configurator - Advanced CSX Settings

Note: You can change the modulator clock frequency to 48 MHz only after changing the IMO clock frequency to 48 MHz. To do this, navigate to the System tab in the Device Configurator tool, and select System Clocks > Input > IMO. Select 48 from the Frequency (MHz) dropdown list.

Set the Tx clock divider and Tx clock source.

Navigate to the Advanced tab and then select the Widget Details sub tab.

Set the Tx clock divider as per the following guidelines:

CAPSENSE™ configurator in ModusToolbox™ software allows you to set the Tx clock frequency in terms of the Tx clock divider as shown in Equation 1.

Equation 1. Ftx divider

Set the Tx clock frequency such that it completely charges and discharges the sensor parasitic capacitance for maximum sensitivity. It can be verified by checking the signal in an oscilloscope or set using Equation 2:

Equation 2. Maximum Tx clock frequency criterion

C_{P_Tx} = Parasitic capacitances of Tx electrodes;

C_{P_Rx} = Parasitic capacitances of Rx electrodes;

R_Series = Recommended external series resistance (connected to the PCB trace connecting sensor pad to the device pin), and trace resistance if using highly resistive materials (for example, ITO or conductive ink).

Calculate the maximum Tx clock frequency

Note: While using this procedure, ensure that you have enabled the Enable self-test library option in the CAPSENSE™ Configurator. After you obtain the Cp value, disable this option.

Estimate the C_p of the Tx and Rx electrodes. Use the Cy_CapSense_MeasureCapacitanceSensor() function to measure the parasitic capacitance (C_p) of the Tx and Rx electrodes of the CSX button. The C_p can also be measured using an LCR meter.
Program the board in Debug mode.

In the IDE, use the <Application Name> Debug (KitProg3_MiniProg4) configuration in the Quick Panel.

For more details, see the "Program and debug" section in the Eclipse IDE for ModusToolbox™ user guide: {ModusToolbox™ software install directory}/ide_{version}/docs/mt_ide_user_guide.pdf.
Place a breakpoint after the capacitance measurement.
In the Expressions window, add the Cp measurement variables tx_cp and rx_cp.

The status of the measurement can also be read through the return value of the function in the Expressions window.
Click Resume (green arrow) to reach the breakpoint.

Note that the function return value reads CY_CAPSENSE_BIST_SUCCESS_E and the measurement variables provide the capacitance of the sensor elements in femtofarads as shown in Figure 4.
Click Terminate (red box) to exit Debug mode.

Figure 4. Cp measurement using BIST

Using BIST, the C_P of the Tx and Rx electrodes are estimated as shown in Table 2. Set the Tx clock divider to the value obtained (using equation 1) in Table 2 in the CAPSENSE™ configurator as shown in Figure 5. Note that for the PSoC™ 4S series, PSoC™ 4100S Plus, and PSoC™ 4100PS family of devices, the maximum F_Tx supported is 3000 kHz.

Table 2. Cp of Tx and Rx electrode, calculated maximum Tx clock frequency, and Tx clock divider setting in CAPSENSE™ configurator

Development kit	Tx pin	Rx pin	Cp of Tx electrode (pF)	Cp of Rx electrode (pF)	External resistance (ohms)	Calculated maximum Tx clock frequency (kHz)	Initial Tx clock divider setting in configurator
CY8CKIT-149	P0.2	P4.6	36	13	2000	1388	35
CY8CKIT-145-40XX	P1.3	P1.4	22	12	560	8116	16
CY8CKIT-041-41XX	P3.7	P0.1	41	49	560	3644	16
CY8CKIT-045S	P0.4	P4.4	23	13	2000	2174	23

Ensure the following in addition to this condition:
- The auto-calibrated IDAC code should lie in the mid-range (for example, 30-90) for the selected F_Tx. If the auto-calibrated IDAC value lies out of the recommended range, F_Tx is tuned such that IDAC falls in the recommended range. See Ensure auto-calibrated IDAC within recommended range.
- If you are using the SSCx clock source, ensure that you select the Tx clock frequency that meets the conditions mentioned in the ModusToolbox™ CAPSENSE™ configurator guide in addition to these conditions.

Set the number of sub-conversions to an initial low value of 20. This will be modified in Stage 3: Modify hardware parameters or adjust filter settings based on the signal-to-noise ratio (SNR) and system timing requirements. Leave all other values in the tab to their default settings.

Figure 5. Advanced tab - Widget Details

Note: The CAPSENSE™ initialization may fail at this stage. Ensure that CAPSENSE™ initialization passes after the final tuning parameters are set.

Program the board using one of the following:
Using Eclipse IDE for ModusToolbox™ software
1. Select the application project in the Project Explorer.
2. In the Quick Panel, scroll down, and click <Application Name> Program (KitProg3_MiniProg4).
Using CLI

From the terminal, execute the make program command to build and program the application using the default toolchain to the default target. The default toolchain is specified in the application's Makefile but you can override this value manually:
```
make program TOOLCHAIN=<toolchain>
```
Example:
```
make program TOOLCHAIN=GCC_ARM
```

Stage 2: Measure SNR

Set up CAPSENSE™ tuner to view sensor data

Launch the CAPSENSE™ tuner.

See the "Launch the CAPSENSE™ tuner" section from the ModusToolbox™ CAPSENSE™ tuner guide.
Go to Tools > Tuner Communication Setup and set the parameters as shown in Figure 6. Click OK.

Figure 6. Tuner Communication Setup
Click Connect.

Figure 7. CAPSENSE™ tuner window
Click Start.

Figure 8. CAPSENSE™ tuner start

The Widget/Sensor Parameters tab gets updated with the parameters configured in the CAPSENSE™ Configurator window.

Figure 9. CAPSENSE™ tuner window
Select the Button0 check box and Synchronized under Read mode, and then navigate to Graph View as shown in Figure 10.

The Graph View displays the raw counts and baseline for Button0_Rx0 in the Sensor data window. Ensure to select the RawCount checkbox and Baseline checkbox to view the sensor data.

Figure 10. CAPSENSE™ tuner - Graph View

Note: At this point, when the configured button is touched, you may or may not notice the touch signal in the Sensor Signal graph. The sensor may false-trigger which can be seen in the touch status going from 0 to 1 in the Status window.

Ensure auto-calibrated IDAC within recommended range

As discussed in step 6 of Stage 1: Set initial hardware parameters, the Tx clock frequency will be tuned to bring the IDAC code to the recommended range in this step. Click Button0 in the Widget Explorer to view the IDAC value in the Sensor Parameters window as shown in Figure 11. If the IDAC value is within the range (30 to 90), skip to step 8 Measure SNR; otherwise, follow step 7 to modify Tx clock divider until the IDAC value is in the desired range.

Figure 11. IDAC value
Fine-tune the Tx clock frequency to bring the IDAC value within range.
1. Click Button0 in the Widget explorer.
2. Increase or decrease the Tx clock divider in the Widget hardware parameters window in steps of 5. Increasing the Tx clock divider (decreases the Tx clock frequency) will decrease the IDAC value for a fixed IDAC gain and calibration percent and vice versa.
3. Click the To Device button to apply the changes to the device as shown in Figure 12.
  
  Figure 12. Apply changes to the device
4. Observe the IDAC value in the Sensing parameters section of the Widget/Sensor Parameters window.
5. Repeat steps 1 to 4 until you obtain the IDAC value in the range of 30 to 90.
After performing these steps, you will arrive at the following Tx clock divider values.

Table 3. Final Tx clock frequency

Development kit Tx clock divider setting in configurator

CY8CKIT-149 60

CY8CKIT-145-40XX 120

CY8CKIT-041-41XX 220

CY8CKIT-045S 32

Development kit	Tx clock divider setting in configurator
CY8CKIT-149	60
CY8CKIT-145-40XX	120
CY8CKIT-041-41XX	220
CY8CKIT-045S	32

Measure SNR

Switch to the SNR Measurement tab, select the Button0_Rx0 sensor, and then click Acquire Noise as shown in Figure 13.

Figure 13. CAPSENSE™ tuner - SNR Measurement: Acquire Noise
Once the noise is acquired, touch the button on the kit, and then click Acquire Signal. Ensure that the finger is on the button as long as the signal acquisition is in progress.

The calculated SNR on this button is displayed, as Figure 14 shows. Based on your end-system design, test with a finger that matches the size of your normal use case. Typically, finger size targets are ~8 to 9 mm.

Figure 14. CAPSENSE™ tuner - SNR Measurement: Acquire Signal

Stage 3: Modify hardware parameters or adjust filter settings

Skip to Stage 4: Set threshold parameters if the following conditions are met:
- Measured SNR from the previous stage (Measure SNR) is greater than 5:1.
- Signal count >50.
- Response time requirements are met.
Perform steps 2 to 4 to ensure that SNR and timing requirements are met. You should tune the buttons for an SNR > 5:1 to avoid triggering on noise, and ensure that all intended touches are registered.

Modify hardware parameters

Increasing the number of sub-conversions increases the signal without increasing the noise at the same rate. Update the number of sub-conversions directly in the Widget/Sensor Parameters tab of the CAPSENSE™ tuner GUI. Increase the number of sub-conversions in steps and repeat steps in the Measure SNR section until the minimum SNR of 5:1 is achieved. However, increasing the number of sub-conversions will in turn increase the sensor scan time as Equation 3 shows:

Equation 3. Hardware scan time of the CSX sensor

NoC = Number of sub-conversions; F_TX = Tx clock frequency

Adjust filter settings

If your system is very noisy (counts >20), add a filter. Filters help reduce the noise without increasing the signal. Adding a filter adds to the processing time and memory usage, because this is implemented in firmware and gets executed by the CPU. This also results in increased power consumption.

To adjust the filter settings, open CAPSENSE™ Configurator and select the appropriate filter in step 4. See Figure 15.
Reprogram the device to update filter settings.

Note: Add the filter based on the type of noise in your measurements. See ModusToolbox™ CAPSENSE™ configurator guide for details.

Figure 15. Firmware filter settings

Use Table 4 to set the filter settings for different development kits:

Table 4. Filter settings for different development kits

Development kit	IIR filter	IIR filter raw count coefficient	Median filter	Average filter
CY8CKIT-041-41XX	Enabled	64	Disabled	Disabled
CY8CKIT-149	Disabled	NA	Disabled	Disabled
CY8CKIT-145-40XX	Disabled	NA	Disabled	Disabled
CY8CKIT-045S	Disabled	NA	Disabled	Disabled

Timing requirements

If the total sensor scan time meets your requirements, skip to Stage 4: Set threshold parameters. If not, adjust the tuning to speed up the scan time. If SNR > 10 on any sensor, lower the number of sub-conversions or remove the filters to decrease the scan time but keep the SNR greater than 5:1. It is best to find a balance between the number of sub-conversions and filters to achieve a proper overall tuning.

Use Table 5 to set the hardware tuning parameters to achieve 5:1 SNR.

Table 5. Final hardware tuning parameters to achieve 5:1 SNR

Development kit	Tx clock divider setting in configurator	Number of sub-conversions
CY8CKIT-149	60	20
CY8CKIT-145-40XX	120	20
CY8CKIT-041-41XX^*	220	30
CY8CKIT-045S	32	30

^*Firmware filters enabled.

Stage 4: Set threshold parameters

After you have confirmed that your design meets the timing parameters, and the SNR is greater than 5:1, set your threshold parameters as follows:

Switch to the Graph View tab and select Button0.
Touch the sensor and monitor the touch signal in the Sensor Signal graph. The Sensor Signal graph should display the signal as Figure 16 shows.

Ensure that you observe the difference count (that is, the signal output) in the Graph View tab in Figure 16, not the raw count output for setting these thresholds. Based on your end system design, test the signal with a finger that matches the size of your normal use case. Typically, finger size targets are ~8 to 9 mm. Consider testing with smaller sizes that should be rejected by the system to ensure that they do not reach the finger threshold.

Figure 16. Sensor signal when the sensor is touched
When the signal is measured, set the thresholds according to the following recommendations:
- Finger threshold = 80 percent of signal
- Noise threshold = 40 percent of signal
- Negative noise threshold = 40 percent of signal
- Hysteresis = 10 percent of signal
- Debounce = 3

Set the threshold parameters in the Widget/Sensor Parameters section of the CAPSENSE™ tuner, as Figure 17 shows:

Figure 17. Widget threshold parameters

See Table 6 to set the threshold parameters in the CAPSENSE™ tuner for different development kits.

Table 6. Threshold parameters for different development kits

Development kit	Difference counts	Finger threshold	Noise threshold	Negative noise threshold	Hysteresis	Low baseline reset	Debounce
CY8CKIT-149	65	56	26	26	7	30	3
CY8CKIT-145-40XX	80	64	32	32	8	30	3
CY8CKIT-041-41XX	65	56	26	26	7	30	3
CY8CKIT-045S	60	48	24	24	6	30	3

Apply the settings to the device and to the project by clicking To Device and then To Project as Figure 18 shows, and close the tuner.

Figure 18. Apply settings to the project
If your sensor is tuned correctly, you will observe the touch status go from 0 to 1 in the Status sub-window of the Graph View tab as Figure 19 shows. The successful tuning of the button is also indicated by a LED in the kit. The user LED is turned ON when the finger touches the button and turned OFF when the finger is removed from the button.

Figure 19. Sensor status window
Launch CAPSENSE™ Configurator. You should now see all the changes that you have made in the CAPSENSE™ tuner reflected in the CAPSENSE™ Configurator.

Debugging

You can debug the example to step through the code. In the IDE, use the <Application Name> Debug (KitProg3_MiniProg4) configuration in the Quick Panel. For details, see the "Program and debug" section in the Eclipse IDE for ModusToolbox™ software user guide.

Design and implementation

The project contains a single button widget configured in CSX sensing mode. See the "CAPSENSE™ CSX sensing method" section in AN85951 – PSoC™ 4 and PSoC™ 6 MCU CAPSENSE™ design guide for details on CAPSENSE™ CSX sensing mode. See the Operation section of this document for step-by-step instructions to configure the other settings of the CAPSENSE™ configurator.

The project uses the CAPSENSE™ middleware (see ModusToolbox™ software user guide for more details on selecting the middleware). See AN85951 – PSoC™ 4 and PSoC™ 6 MCU CAPSENSE™ design guide for more details on CAPSENSE™ features and usage.

The ModusToolbox™ software provides a GUI-based tuner application for debugging and tuning the CAPSENSE™ system. The CAPSENSE™ tuner application works with the EZI2C and UART communication interfaces. This project has an SCB block configured in EZI2C mode to establish communication with the onboard KitProg, which in turn enables reading the CAPSENSE™ raw data by the CAPSENSE™ tuner GUI. See Resources and settings.

The CAPSENSE™ data structure that contains the CAPSENSE™ raw data is exposed to the CAPSENSE™ tuner by setting up the I2C communication data buffer with the CAPSENSE™ data structure. This enables the CAPSENSE™ tuner to access the CAPSENSE™ raw data for tuning and debugging.

The successful tuning of the button is indicated by a user LED in the kit. The LED is turned ON when the finger touches the button and turned OFF when the finger is removed from the button.

Resources and settings

Figure 20. EZI2C settings

Table 7. Application resources

Resource	Alias/object	Purpose
SCB (I2C) (PDL)	CYBSP_EZI2C	EZI2C slave driver to communicate with CAPSENSE™ tuner
CAPSENSE™	CYBSP_CSD	CAPSENSE™ driver to interact with the CSD hardware and interface CAPSENSE™ sensors
GPIO (PDL)	CYBSP_BTN0_LED	To indicate the button status

Related resources

Resources	Links
Application notes	AN79953 – Getting started with PSoC™ 4 AN85951 – PSoC™ 4 and PSoC™ 6 MCU CAPSENSE™ design guide
Code examples	Using ModusToolbox™ software on GitHub Using PSoC™ Creator
Device documentation	PSoC™ 4 datasheets PSoC™ 4 technical reference manuals
Development kits	Select your kits from the evaluation board finder.
Libraries on GitHub	mtb-pdl-cat2 – PSoC™ 4 peripheral driver library (PDL) mtb-hal-cat2 – Hardware abstraction layer (HAL) library
Middleware on GitHub	capsense – CAPSENSE™ library and documents
Tools	ModusToolbox™ software – ModusToolbox™ software is a collection of easy-to-use software and tools enabling rapid development with Infineon MCUs, covering applications from embedded sense and control to wireless and cloud-connected systems using AIROC™ Wi-Fi and Bluetooth® connectivity devices. PSoC™ Creator – IDE for PSoC™ and FM0+ MCU development

Other resources

Infineon provides a wealth of data at www.infineon.com to help you select the right device, and quickly and effectively integrate it into your design.

Document history

Document title: CE230660 - PSoC™ 4: CAPSENSE™ CSX button tuning

Version	Description of change
1.0.0	New code example
2.0.0	Major update to support ModusToolbox™ software v2.2, added support for new kits This version is not backward compatible with ModusToolbox™ software v2.1
3.0.0	Major update to support ModusToolbox™ software v2.4 and updated to use CAPSENSE™ MW 3.X Added support for CY8CKIT-045S kit This version is not backward compatible with ModusToolbox™ software v2.3
4.0.0	Major update to support ModusToolbox™ v3.0 This version is not backward compatible with previous versions of ModusToolbox™
4.1.0	Update to support ModusToolbox™ v3.1 and CAPSENSE™ middleware v4.X

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mtb-example-psoc4-capsense-csx-button-tuning/README.md