PSOC™ 4: MSCLP CAPSENSE™ liquid level sensing

This code example demonstrates an implementation of capacitive sensors to measure the depth of water-based liquids in nonconductive containers. Mounted on or near the container exterior, these sensors provide accurate, real-time monitoring of liquid fill levels, while also rejecting foam interference and eliminating the need for physical contact with the liquid.

View this README on GitHub.

Provide feedback on this code example.

Requirements

ModusToolbox™ v3.4 or later (tested with v3.4)

Note: This code example requires ModusToolbox™ v3.4 and is not backward compatible with v3.3 or older.
Board support package (BSP) minimum required version: 3.2.0
Programming language: C
Associated parts: PSOC™ 4000T

Supported toolchains (make variable 'TOOLCHAIN')

GNU Arm® Embedded Compiler v11.3.1 (GCC_ARM) – Default value of TOOLCHAIN
Arm® Compiler v6.22 (ARM)
IAR C/C++ Compiler v9.50.2 (IAR)

Supported kits (make variable 'TARGET')

PSOC™ 4000T Multisense Control Board (CY8CPROTO-040T-MS) – Default value of TARGET

Hardware setup

This example uses the liquid level sensing kit with the multisense control board's default configuration. See the kit user guide to ensure that the board is configured correctly.

Note: Some PSOC™ 4 kits ship with KitProg2 installed. ModusToolbox™ 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 If you do not upgrade, you will see an error like "unable to find CMSIS-DAP device" or "KitProg firmware is out of date".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

See the ModusToolbox™ tools package installation guide for information about installing and configuring the tools package.

This example requires ModusToolbox™ CAPSENSE™ and Multi-Sense Pack to be installed.

Using the code example

Create the project

The ModusToolbox™ tools package provides the Project Creator as both a GUI tool and a command line tool.

Use Project Creator GUI

Open the Project Creator GUI tool.

There are several ways to do this, including launching it from the dashboard or from inside the Eclipse IDE. For more details, see the Project Creator user guide (locally available at {ModusToolbox™ install directory}/tools_{version}/project-creator/docs/project-creator.pdf).
On the Choose Board Support Package (BSP) page, select a kit supported by this code example. See Supported kits.

Note: To use this code example 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.
On the Select Application page:

a. Select the Applications(s) Root Path and the Target IDE.

Note: Depending on how you open the Project Creator tool, these fields may be pre-selected for you.

b. Select this code example from the list by enabling its check box.

Note: You can narrow the list of displayed examples by typing in the filter box.

c. (Optional) Change the suggested New Application Name and New BSP Name.

d. Click Create to complete the application creation process.

Use Project Creator CLI

The 'project-creator-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™ 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™ installation instead of a standard Windows command-line application. This shell provides access to all ModusToolbox™ 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 following example clones the "PSOC™ 4: MSCLP CAPSENSE™ liquid level sensing" application with the desired name "MyLLS" configured for the CY8CPROTO-040T-MS BSP into the specified working directory, C:/mtb_projects:

project-creator-cli --board-id CY8CPROTO-040T-MS --app-id mtb-example-psoc4-msclp-lls --user-app-name MyLLS --target-dir "C:/mtb_projects"

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

Argument	Description	Required/optional
`--board-id`	Defined in the field of the BSP manifest	Required
`--app-id`	Defined in the 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

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™ tools package user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mtb_user_guide.pdf).

Open the project

After the project has been created, you can open it in your preferred development environment.

Eclipse IDE

If you opened the Project Creator tool from the included Eclipse IDE, the project will open in Eclipse automatically.

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

Visual Studio (VS) Code

Launch VS Code manually, and then open the generated {project-name}.code-workspace file located in the project directory.

For more details, see the Visual Studio Code for ModusToolbox™ user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mt_vscode_user_guide.pdf).

Keil µVision

Double-click the generated {project-name}.cprj file to launch the Keil µVision IDE.

For more details, see the Keil µVision for ModusToolbox™ user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mt_uvision_user_guide.pdf).

IAR Embedded Workbench

Open IAR Embedded Workbench manually, and create a new project. Then select the generated {project-name}.ipcf file located in the project directory.

For more details, see the IAR Embedded Workbench for ModusToolbox™ user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mt_iar_user_guide.pdf).

Command line

If you prefer to use the CLI, open the appropriate terminal, and navigate to the project directory. On Windows, use the command-line 'modus-shell' program; on Linux and macOS, you can use any terminal application. From there, you can run various make commands.

For more details, see the ModusToolbox™ tools package user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mtb_user_guide.pdf).

Operation

Ensure the PSOC™ 4000T Multisense Control Board is connected with the Liquid Level Sensing Flex PCB.

Note: If a custom container is used other than the bottle provided with the kit, the system may need a Factory Calibration as menitoned in the section Factory calibration.
Connect the board to your PC using the provided USB cable through the KitProg3 USB connector.
Program the board using one of the following:
Using Eclipse IDE
1. Select the application project in the Project Explorer.
2. In the Quick Panel, scroll down, and click <Application Name> Program (KitProg3_MiniProg4).
In other IDEs

Follow the instructions in your preferred IDE.
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
```
After programming, the application starts automatically.

Note: After programming, you see the following error message if debug mode is disabled. This can be ignored or enabling the debug mode will solve this error.
```
"Error: Error connecting Dp: Cannot read IDR"
```

Monitor data using CAPSENSE™ Tuner

Open CAPSENSE™ Tuner from the Tools section in the IDE Quick Panel.

You can also run the CAPSENSE™ Tuner application in standalone mode from {ModusToolbox™ install directory}/ModusToolbox/tools_{version}/capsense-configurator/capsense-tuner. In this case, after opening the application, select File > Open and open the design.cycapsense file of the respective application, which is present in the {Application root directory}/bsps/TARGET_APP_<BSP-NAME>/config folder.

See the ModusToolbox™ user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mtb_user_guide.pdf) for options to open the CAPSENSE™ Tuner application using the CLI.
Ensure that the status LED is on and not blinking. This indicates that the onboard KitProg3 is in CMSIS-DAP bulk mode. See Firmware-loader to learn how to update the firmware and switch modes in KitProg3.
In the Tuner application, click on the Tuner Communication Setup icon or select Tools > Tuner Communication setup.

In the window that appears, select I2C under KitProg3 and configure it as follows:
- I2C address: 8
- Sub-address: 2-Bytes
- Speed (kHz): 400
These are the same values set in the EZI2C resource.

Figure 1. Tuner Communication Setup parameters
Click Connect or select Communication > Connect to establish a connection.

Figure 2. Establish connection
Click Start or select Communication > Start to start data streaming from the device.

Figure 3. Start tuner communication

The Widget/Sensor Parameters tab is updated with the parameters configured in the CAPSENSE™ Configurator window. The tuner displays the data from the sensor in Widget View and Graph View tabs.
Set the Read mode to Synchronized. Navigate to the Widget View tab and observe the needle in the Liquid_Level_Sensor_FR widget is changing as you pour or remove water in the container.

Figure 4. Widget view of the CAPSENSE™ Tuner
Add a layer of foam on top of the liquid, facilitated by a surfactant, and observe how the liquid level remains unaffected by the foam, as reported by the Liquid_Level_Sensor_FR widget. This demonstrates the system's ability to reject foam and maintain accurate liquid level sensing.

Figure 5. Widget view of the CAPSENSE™ Tuner

Note: The Level in the Liquid_Level_Sensor changes due to the foam as it is a normal liquid level sensor and does not incorporate the foam rejection capability.
View the raw counts of the liquid level sensors through the Graph View tab. The normal liquid level and foam-rejected liquid level can be observed in the position window.

Figure 6. Liquid Level Sensor position
Switch to the SNR Measurement tab and verify that the SNR is above 20:1 by performing the following steps.
1. Select the Liquid_Level_0_Sns0 sensor under the Liquid_Level_0 widget and click Acquire Noise, as shown in Figure 7. Repeat the same (Acquire Noise) for all sensors under the Liquid_Level_0 widget.
  
  Figure 7. CAPSENSE™ Tuner - SNR measurement: Acquire noise
2. Fill the tank to the maximum level, Select the Liquid_Level_0_Sns0 sensor under the Liquid_Level_0 widget, and click Acquire Signal, as shown in Figure 8 and wait for the SNR measurement to complete. Repeat the same (Acquire Signal) for all the sensors under the Liquid_Level_0 widget.
  
  Figure 8. CAPSENSE™ Tuner - SNR measurement: Acquire signal
  
  Ensure that the SNR is above 20:1.

Tuning Procedure

Create custom BSP for your board

Create a custom BSP for your board with any device by following the steps given in ModusToolbox™ BSP Assistant user guide. This code example is created for the CY8C4046LQI-T452 device.
Open the design.modus file from the {Application root directory}/bsps/TARGET_APP_<BSP-NAME>/config/ folder obtained in the previous step and enable CAPSENSE™ to get the design.cycapsense file. CAPSENSE™ configuration can be started from scratch as follows:

Note: See the section Selecting CAPSENSE™ hardware parameters in AN85951 PSOC™ 4 and PSOC™ 6 MCU CAPSENSE™ design guide to learn the considerations for selecting each parameter value.

The tuning flow of the Liquid Level Sensing Widget is shown below.

Figure 9. Tuning Flow of Liquid Level Sensor

Perform the following to tune the Liquid Level Sensing Widget:

Stage 1: Set the initial hardware parameters
Stage 2: Set the sense clock frequency
Stage 3: Fine tune for the required SNR

Stage 1: Set the initial hardware parameters

Connect the board to your PC using the provided USB cable through the KitProg3 USB connector.
Launch the Device Configurator tool.

You can launch the Device Configurator in Eclipse IDE for ModusToolbox™ from the Tools section in the IDE Quick Panel or in standalone mode from {ModusToolbox™ install directory}/ModusToolbox/tools_{version}/device-configurator/device-configurator. In this case, after opening the application, select File > Open and open the design.modus file of the respective application located in the {Application root directory}/bsps/TARGET_APP_<BSP-NAME>/config folder.
Enable the CAPSENSE™ channel in the Device Configurator as shown in Figure 10:

Figure 10. Enable CAPSENSE™ in Device Configurator

Save the changes and close the window.
Launch the CAPSENSE™ Configurator tool.

You can launch the CAPSENSE™ Configurator tool in Eclipse IDE for ModusToolbox™ from the "CAPSENSE™" peripheral setting in the Device Configurator or directly from the Tools section in the IDE Quick Panel.

You can also launch it in standalone mode through {ModusToolbox™ install directory}/ModusToolbox/tools_{version}/capsense-configurator/capsense-configurator. In this case, after opening the application, select File > Open and open the design.cycapsense file of the respective application present in the {Application root directory}/bsps/TARGET_APP_<BSP-NAME>/config folder.

See the ModusToolbox™ CAPSENSE™ Configurator user guide for step-by-step instructions on how to configure and launch CAPSENSE™ in ModusToolbox™.
In the Basic tab, configure a Liquid Level Sensing widget as a CSD RM (self-cap). The Liquid Level sensing widget comprises a number of sensing elements called segments. The widget uses the data from each segment to calculate the liquid level.

Figure 11. CAPSENSE™ Configurator - Basic tab

Do the following in the General tab under the Advanced tab:

Table 1. Widget details

Parameter	Setting	Comment
CAPSENSE™ IMO Clock frequency	46	IMO clock Frequency
Modulator clock divider	1	Set to obtain the optimum modulator clock frequency
Number of init sub-conversions	3	Set to ensure proper initialization of CAPSENSE™
Enable CIC2 hardware filter	TRUE	Enabling CIC2 filter helps in higher SNR

Figure 12. CAPSENSE™ Configurator - General settings

Go to the CSD Settings tab and make the following changes:

Table 2. Scan settings

Parameter	CY8CPROTO-040T-MS	Comment
Inactive sensor connection	Shield	Connects the inactive sensors (configured sensors which have not been scanned in a given scan-slot) to the driven shield.
Shield mode	Active	The driven shield is a signal that replicates the sensor-switching signal. It helps reduce the sensor parasitic capacitance.
Total shield count	2	Selects the number of shield electrodes used in the design. Most designs work with one dedicated shield electrode, but some designs require multiple dedicated shield electrodes to ease the PCB layout routing or minimize the PCB area used for the shield layer.
Raw count calibration level (%)	40	If the sensor raw count saturates (equals max raw count) on water covering the sensor, reduce the raw count calibration level (%). This will prevent raw count saturation.

Figure 13. CAPSENSE™ Configurator - Advanced CSD settings

Go to the Widget Details tab.

Select the LiquidLevel0 from the left pane and set the following:

Table 4. Initial widget parameter setting LiquidLevel0

Parameter	Setting	Comment
Enable foam rejection	true	This is to enable the Foam Rejection Widget for the Foam Rejection functonality
Maximum Level	120	Set this value to a multiple of the total depth of the tank. For example, this project uses a 12 cm tank, hence the value may be 120, 240, or 1200; however, this project has used 120, for every 1 count 1 mm will be measured.
Sense clock divider	Default	Value will be set in Stage 2: Set sense clock frequency
Clock source	Direct	Direct clock is a constant frequency sense clock source. When you choose this option, the sensor pin switches with a constant frequency.
Number of sub-conversions	60	Good starting point to ensure a fast scan time and sufficient signal. This value has to be adjusted as required in Stage 3: Fine-tune for required SNR, power, and refresh rate.
Reference CDAC Mode	Auto	Setting it to Auto for initial Auto Calibration
Reference CDAC Boost	Disabled	Not required
Fine CDAC Mode	Auto	Setting it to Auto for initial Auto Calibration
Compensation CDAC Mode	Auto	Setting it to Auto for initial Auto Calibration
Compensation CDAC divider Mode	Auto	Setting it to Auto for initial Auto Calibration
CDAC dither mode	Disabled	Not required
IIR Filter	False	Not required
Median filter	true	Essential to remove sudden spikes in the level measurement due to calculation errors
Average Filter	true	Removes periodic noises like noise from AC mains
Jitter Filter	true	Removes toggling of the position data

Figure 14. CAPSENSE™ Configurator - Liquid Level Sensor Widget Details

Select the LiquidLevel0_FR from the left pane and set the following:

Table 5. Initial widget parameter setting LiquidLevel0_FR

Parameter	Setting	Comment
Foam Correction Coefficient	64	This is to compensate the foam correction level. To accurately calculate this value, follow the steps mentioned in Section 6.2: Foam rejection calibration of AN239805.
Maximum Level	Same as LiquidLevel0 widget	-
Sense clock divider	Same as LiquidLevel0 widget	-
Clock source	Same as LiquidLevel0 widget	-
Number of sub-conversions	2X of the LiquidLevel0	General guidance is to set the number of sub-conversions to twice the number of sub-conversions for the base widget.
Reference CDAC Mode	Auto	Setting it to Auto for initial Auto Calibration
Reference CDAC Boost	Disabled	Not required
Fine CDAC Mode	Auto	Setting it to Auto for initial Auto Calibration
Compensation CDAC Mode	Auto	Setting it to Auto for initial Auto Calibration
Compensation CDAC divider Mode	Auto	Setting it to Auto for initial Auto Calibration
CDAC dither mode	Disabled	Not required
IIR Filter	False	Not required
Median filter	true	Essential to remove sudden spikes in the level measurement due to calculation errors
Average Filter	true	Removes periodic noise like noise from AC mains
Jitter Filter	true	Removes toggling of the position data

Figure 15. CAPSENSE™ Configurator - Liquid Level Foam Rejection Widget Details

Go to the Scan Configuration tab to select the pins and scan slots. Configure the pins for electrodes using the drop-down menu. Ensure that the bottom most sensor is considered as Sensor 0 (Sns0) and the top most sensor is considered as Sensor N (SnsN).
The electrodes for the Liquid Level Foam rejection widget LiquidLevel0_FR are same as that of the Liquid Level Widget LiquidLevel0. So the sensor electrodes of LiquidLevel0 are simply ganged to LiquidLevel0_FR widget's sensor electrodes.

Figure 16. CAPSENSE™ Configurator - Scan Configuration tab

Stage 2: Set sense clock frequency

The sense clock is derived from the modulator clock using a sense clock divider and is used to scan the sensor by driving the CAPSENSE™ switched capacitor circuits. Both the clock source and clock divider are configurable. The sense clock divider should be configured so that the pulse width of the sense clock is long enough to let the sensor capacitance charge and discharge completely. This is verified by observing the charging and discharging waveforms of the sensor using an oscilloscope and an active probe. The sensors should be probed close to the electrode and not at the sense pins or the series resistor.

See Figure 17 and Figure 18 for waveforms observed on the sensors. Figure 17 shows proper charging when the sense clock frequency is correctly tuned. Adjust the sense clock divider so that the voltage is reaching at least 99.3 percent of VDDD in Phase 1, or VDDD/2 in Phase 0, as Figure 18 shows.

Figure 17. Proper charge cycle of a sensor

Figure 18. Improper charge cycle of a sensor

To set the proper sense clock frequency, follow these steps:

Program the board and launch CAPSENSE™ Tuner.
Observe the charging waveform of the sensor and shield as described earlier.
If the charging is incomplete, increase the sense clock divider. Do this in CAPSENSE™ Tuner by selecting the widget and editing the sense clock divider parameter in the Widget/Sensor Parameters panel.

Note: - The sense clock divider should be divisible by 4. This ensures that all four scan phases have equal durations. - After editing the value, click the Apply to Device button and observe the waveform again. Repeat this until you observe complete settling. - Using a passive probe will add an additional parasitic capacitance of around 15 pF; therefore, it should be considered while tuning.
Click Apply to Project to save the configuration to your project.

Figure 19. Sense clock divider setting
Repeat this process for all the sensors and the shield. Each sensor may require a different sense clock divider value to charge or discharge completely. But all the sensors under the same widget need to have the same sense clock source, sense clock divider, and number of sub-conversions. Therefore, consider the largest sense clock divider required by the sensor for that widget.

Note: Typically, shields require a high sense clock divider. Because this project utilizes a shield, obtain the required sense clock divider for the shield. If it is higher than the Liquid Level Sensor widget, set the same sense clock divider for the Liquid Level Sensor Widget as well.

Table 7. Sense clock divider settings obtained for supported kits

Parameter CY8CPROTO-040T-MS

Sense clock divider 128

Parameter	CY8CPROTO-040T-MS
Sense clock divider	128

Stage 3: Fine tune for required SNR

The sensor must provide a large signal for the processing function to accurately calculate the liquid level. Liquid level sensing systems perform best with signal-to-noise ratio (SNR) values 10 or higher. The sensitivity can be increased by increasing the number of sub-conversions and noise can be decreased by enabling available filters. This section demonstrates using CAPSENSE™ Tuner and Configurator to measure and adjust the SNR.

Follow these steps for optimizing these parameters:

Measure the SNR as mentioned in Step 9 of the Operation section.
If the SNR is less than 20:1, increase the number of sub-conversions. Edit the number of sub-conversions (N_sub) directly in the Widget/Sensor parameters tab of the CAPSENSE™ Tuner and click on Apply to Device.

Note: Number of sub-conversion should be greater than or equal to 8.
Repeat steps 1 and 2 until the Measured SNR is greater than 20:1
If the system is noisy (>40% of signal), enable filters.

Enable the IIR filter for noise reduction.

To enable and configure filters available in the system:

a. Open CAPSENSE™ Configurator from ModusToolbox™ Quick Panel and select the appropriate filter.

Figure 20. Filter settings in CAPSENSE™ Configurator

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

b. Click Save and close CAPSENSE™ Configurator. Program the device to update the filter settings.

Note : Increasing the number of sub-conversions and enabling filters increases the scan time, which in turn reduces sensor responsiveness and increases power consumption. Therefore, the number of sub-conversions and filter configuration must be optimized to achieve a balance between SNR, power, and refresh rate.

Factory calibration

All CAPSENSE™-based liquid level sensing solutions require a one-time calibration procedure using a known water level. This code example is pre-calibrated to use with the Liquid Level Sensing Kit with a calibrated range of 120 mm and a resolution of 1 mm. The one-time calibration procedure is outlined in Section 6: Liquid-level Factory calibration procedure of of AN239805.

Debugging

You can debug the example to step through the code.

In Eclipse 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™ user guide.

In other IDEs

Follow the instructions in your preferred IDE.

Design and implementation

The project uses CAPSENSE™ middleware; see the ModusToolbox™ user guide for more details on selecting a middleware.

See AN85951 - PSOC™ 4 and PSOC™ 6 MCU CAPSENSE™ design guide for more details on CAPSENSE™ features and usage.

See AN239805 for complete details on how to create a liquid level sensing system using CAPSENSE™. It also discusses how to design the liquid level sensors.

This code example uses a Liquid Level Sensing Widget along with it's sub-widget Liquid Level Sensing Foam Rejection Widget to accurately measure the liquid level in the bottle as provided with the Liquid Level Sensing Kit. The Liquid Level Sensing Foam Rejection sub-widget provides accurate liquid level measurements while rejecting foam interference.

Figure 21. Liquid Level Sensor Widget

Figure 22. Liquid Level Sensor Foam Rejection Sub-Widget

The design also has an EZI2C peripheral. The EZI2C slave peripheral is used to monitor the information of a sensor's raw and processed data on a PC using the CAPSENSE™ Tuner available in the Eclipse IDE for ModusToolbox™ via I2C communication.

The Firmware scans the Liquid Level Sensing widget and the Liquid Level Sensing Foam Rejection sub-widget indefinitely. The scan results are then processed and sent to the CAPSENSE™ Tuner via the EZI2C bus. The level then can be seen under the Position window of the CAPSENSE™ Tuner.

Note : In the current project, the Liquid Level Sensing widget and the Liquid Level Sensing Foam Rejection sub-widget are scanned separately and needs to be scanned separately — they will not work if scanned together by calling Cy_CapSense_ScanAllWidgets due to architectural limitations. This will get resolved in upcoming releases.

Set up the VDDA supply voltage and debug mode in Device Configurator

Open Device Configurator from the Quick Panel.
Go to the System tab. Select the Power resource, and set the VDDA value under Operating conditions as shown in Figure 28.

Figure 23. Setting the VDDA supply in the System tab of Device Configurator
Enable debug mode to enable SWD pins, as shown in Figure 24.

Figure 24. Enable debug mode in the System tab of Device Configurator

Resources and settings

Figure 25. EZI2C settings

Table 8. Application resources

Resource	Alias/object	Purpose
SCB (EZI2C) (PDL)	CYBSP_EZI2C	EZI2C slave driver to communicate with CAPSENSE™ Tuner
CAPSENSE™ (MSCLP0)	CYBSP_MSCLP0	CAPSENSE™ driver to interact with the MSCLP hardware and interface the CAPSENSE™ sensors

Firmware flow

Figure 26. Firmware flowchart

Related resources

Resources	Links
Application notes	AN79953 – Getting started with PSOC™ 4 AN85951 – PSOC™ 4 and PSOC™ 6 MCU CAPSENSE™ design guide AN239805 – Liquid-level sensing with PSOC™ 4 CAPSENSE™ AN234231 – Achieving lowest-power capacitive sensing with PSOC™ 4000T AN92239 – Proximity sensing with CAPSENSE™
Code examples	Using ModusToolbox™ on GitHub
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)
Middleware on GitHub	capsense – CAPSENSE™ library and documents psoc4-middleware – Links to all PSOC™ 4 middleware
Tools	ModusToolbox™ – ModusToolbox™ software is a collection of easy-to-use libraries and tools enabling rapid development with Infineon MCUs for applications ranging from wireless and cloud-connected systems, edge AI/ML, embedded sense and control, to wired USB connectivity using PSOC™ Industrial/IoT MCUs, AIROC™ Wi-Fi and Bluetooth® connectivity devices, XMC™ Industrial MCUs, and EZ-USB™/EZ-PD™ wired connectivity controllers. ModusToolbox™ incorporates a comprehensive set of BSPs, HAL, libraries, configuration tools, and provides support for industry-standard IDEs to fast-track your embedded application 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: CE240535 – PSOC™ 4: MSCLP CAPSENSE™ liquid level sensing

Version	Description of change
1.0.0	New code example
2.0.0	Major update to support ModusToolbox™ v3.3. This version is not backward compatible with previous versions of ModusToolbox™
2.1.0	Removed Foam rejection Calibration process

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