TCP server

This code example demonstrates the implementation of a TCP server with PSoC™ 6 MCU with AIROC™ CYW43xxx Wi-Fi & Bluetooth® combo chips. In this example, the TCP server establishes a connection with a TCP client. After the successful connection, the server allows the user to send LED ON/OFF command to the TCP client and the client responds by sending an acknowledgement message to the server. Additionally, this code example can be configured to bring up the Wi-Fi device either in STA interface or Soft AP interface mode.

This example uses the Wi-Fi Core FreeRTOS lwIP mbedtls library of the SDK. This library enables application development based on Wi-Fi by pulling wifi-connection-manager, FreeRTOS, lwIP, mbed TLS, secure sockets, and other dependent modules. The secure sockets library provides an easy-to-use API by abstracting the network stack (lwIP) and the security stack (mbed TLS).

This example can be modified to use ThreadX and NetX Duo instead of FreeRTOS and lwIP. See the Design and implementation section for more details.

View this README on GitHub.

Provide feedback on this code example.

Requirements

• ModusToolbox™ v3.1 or later (tested with v3.1)
• Board support package (BSP) minimum required version: 4.0.0
• Programming language: C
• Associated parts: All PSoC™ 6 MCU parts, AIROC™ CYW20819 Bluetooth® & Bluetooth® LE SoC, AIROC™ CYW43012 Wi-Fi & Bluetooth® combo chip, AIROC™ CYW4343W Wi-Fi & Bluetooth® combo chip, AIROC™ CYW4373 Wi-Fi & Bluetooth® combo chip, AIROC™ CYW43439 Wi-Fi & Bluetooth® combo chip,AIROC™ CYW43439 Wi-Fi & Bluetooth® combo chip, AIROC™ CYW43022 Wi-Fi & Bluetooth® combo chip

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™ 6 Wi-Fi Bluetooth® Prototyping Kit (CY8CPROTO-062-4343W) – Default value of TARGET
• PSoC™ 6 Wi-Fi Bluetooth® Pioneer Kit (CY8CKIT-062-WIFI-BT)
• PSoC™ 62S2 Wi-Fi Bluetooth® Pioneer Kit (CY8CKIT-062S2-43012)
• PSoC™ 62S1 Wi-Fi Bluetooth® Pioneer Kit (CYW9P62S1-43438EVB-01)
• PSoC™ 62S1 Wi-Fi Bluetooth® Pioneer Kit (CYW9P62S1-43012EVB-01)
• PSoC™ 62S3 Wi-Fi Bluetooth® Prototyping Kit (CY8CPROTO-062S3-4343W)
• PSoC™ 64 "Secure Boot" Wi-Fi Bluetooth® Pioneer Kit (CY8CKIT-064B0S2-4343W)
• PSoC™ 62S2 Evaluation Kit (CY8CEVAL-062S2-LAI-4373M2, CY8CEVAL-062S2-MUR-43439M2,CY8CEVAL-062S2-CYW43022CUB)

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™ 6 Wi-Fi Bluetooth® Pioneer Kit (CY8CKIT-062-WIFI-BT) ships 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

1. Install a terminal emulator if you don't have one. Instructions in this document use Tera Term.

2. Install a Python interpreter if you don't have one. This code example is tested using Python 3.7.7.

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

1. 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).

2. 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.

3. 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 "mtb-example-wifi-tcp-server" application with the desired name "WifiScan" configured for the CY8CPROTO-062S2-43439 BSP into the specified working directory, C:/mtb_projects:

project-creator-cli --board-id CY8CPROTO-062S2-43439 --app-id mtb-example-wifi-tcp-server --user-app-name WifiScan --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

If using a PSoC™ 64 "Secure" MCU kit (like CY8CKIT-064B0S2-4343W), the PSoC™ 64 device must be provisioned with keys and policies before being programmed. Follow the instructions in the "Secure Boot" SDK user guide to provision the device. If the kit is already provisioned, copy-paste the keys and policy folder to the application folder.

Note: Use policy_single_CM0_CM4_smif_swap.json policy instead of using the default one "policy_single_CM0_CM4_swap.json" to provision CY8CKIT-064B0S2-4343W device.

1. Connect the board to your PC using the provided USB cable through the KitProg3 USB connector.

2. The kit can be configured to run either in the Wi-Fi STA or AP interface modes. Configure the interface mode using the USE_AP_INTERFACE macro defined in the tcp_server.c file. Based on the desired interface mode, do the following:

   Kit in STA mode (default interface):

   1. Set the USE_AP_INTERFACE macro to '0'; default mode.

   2. Modify the WIFI_SSID, WIFI_PASSWORD, and WIFI_SECURITY_TYPE macros to match the Wi-Fi network credentials that you want to connect to in the tcp_server.c file. Ensure to configure your connecting Wi-Fi network as a private network for the proper functioning of this example.

   Kit in AP mode:

   1. Set the USE_AP_INTERFACE macro to '1'.

   2. (Optional) Update the SOFTAP_SSID, SOFTAP_PASSWORD, and SOFTAP_SECURITY_TYPE as desired.

3. Open a terminal program and select the KitProg3 COM port. Set the serial port parameters to 8N1 and 115200 baud.

4. 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
   

   Figure 1. Wi-Fi interface in STA mode

   

   
   

   Figure 2. Wi-Fi interface in AP mode

   

5. Connect your PC to the Wi-Fi AP that you have configured in Step 2.

   • In STA mode: Connect the PC to the same AP to which the kit is connected.

   • In AP mode: Connect the PC to the kit's AP.

   Note the IP address assigned to the kit as shown in Figure 1 (for STA mode) and Figure 2 (for AP mode).

6. Open the tcp_client.py script located in the {project directory} in a text editor and update the IP address with the IP address assigned to your kit (as noted in Step 5).

   For example, if the IP address assigned to your kit is 192.168.10.1, update the following line in the tcp_client.py script:

   DEFAULT_IP   = '192.168.10.1'
   

7. From the project directory, open a command shell and run the Python TCP client (tcp_client.py). In the command shell opened in the project directory, type in the following command:

     python tcp_client.py
   

   Note: Ensure that the firewall settings of your PC allow access to the Python software so that it can communicate with the TCP server. For more details on enabling Python access, see the community thread.

8. Press the user button (CYBSP_USER_BTN) to send LED ON/OFF command to the Python TCP client. Each user button press will issue the LED ON/OFF commands alternately. The client, in turn, sends an acknowledgement message back to the server. Figure 3 and Figure 4 show the TCP server in STA and AP modes respectively. Figure 5 shows the corresponding TCP client output.

   Figure 3. TCP server output in STA mode

   

   
   

   Figure 4. TCP server output in AP mode

   

   
   

   Figure 5. TCP client output

   

   Note: Instead of using the Python TCP client (tcp_client.py), you can use the example mtb-example-wifi-tcp-client to run as the TCP client on a second kit. See the code example documentation.

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.

Note: (Only while debugging) On the CM4 CPU, some code in main() may execute before the debugger halts at the beginning of main(). This means that some code executes twice - once before the debugger stops execution, and again after the debugger resets the program counter to the beginning of main(). See KBA231071 to learn about this and for the workaround.

Design and implementation

Resources and settings

Table 1. Application resources

Resource	Alias/object	Purpose
SDIO (HAL)	sdio_obj	SDIO interface for Wi-Fi connectivity
UART (HAL)	cy_retarget_io_uart_obj	UART HAL object used by Retarget-IO for the Debug UART port
BUTTON (BSP)	CYBSP_USER_BTN	User button to send LED ON/OFF commands to the TCP client

This example uses the Arm® Cortex®-M4 (CM4) CPU of PSoC™ 6 MCU to execute an RTOS task: TCP server task. At device reset, the default Cortex®-M0+ (CM0+) application enables the CM4 CPU and configures the CM0+ CPU to go to sleep.

In this example, the TCP server establishes a connection with a TCP client. After the successful connection, the server allows the user to send LED ON/OFF command to the TCP client; the client responds by sending an acknowledgement message to the server.

Note: The CY8CPROTO-062-4343W board shares the same GPIO for the user button (CYBSP_USER_BTN) and the CYW4343W host wakeup pin. Because this example uses the GPIO for interfacing with the user button, the SDIO interrupt to wake up the host is disabled by setting CY_WIFI_HOST_WAKE_SW_FORCE to '0' in the Makefile through the DEFINES variable.

Using ThreadX and NetX Duo

This code example can be modified to use the ThreadX and NetX Duo instead of the default FreeRTOS and lwIP. All the source and configuration files required by both the RTOSes are already present in their COMPONENT_* folders. By default, the FreeRTOS and lwIP libraries are added as dependencies in this code example. Follow these steps to configure the code example to use ThreadX and NetX Duo instead.

Adding ThreadX and NetX Duo libraries

1. In the Quick Panel, scroll down, and click Library Manger <version>.
2. In the Library Manager window, delete the wifi-core-freertos-lwip-mbedtls library. This will delete all the dependent libraries as well.
3. Click the Add Library button and add the following libraries back. This step requires a bundle repo for ThreadX, NetX Duo, and NetX Secure does not exist.

   abstraction-rtos
   clib-support
   connectivity-utilities
   netxduo-network-interface-integration
   secure-sockets
   whd-bsp-integration
   wifi-connection-manager
   wifi-host-driver
   

4. Click OK and Update. After the libraries are updated, click Close.
5. The ThreadX and NetX Duo libraries do not show up in the library manager as these are not distributed by Infineon. Add these libraries manually. To add the ThreadX library, create a file called threadx.mtb in the deps folder of the code example with the following content:

https://github.com/azure-rtos/threadx#v6.1.5_rel#$$ASSET_REPO$$/threadx/v6.1.5_rel

6. To add the NetX Duo library, create a file called netxduo.mtb in the deps folder with the following content:

https://github.com/azure-rtos/netxduo#v6.2.0_rel#$$ASSET_REPO$$/netxduo/v6.2.0_rel

7. From the Terminal window, execute the make getlibs command to fetch these libraries.

Makefile changes

1. Change the following lines from

COMPONENTS=FREERTOS

to

COMPONENTS=THREADX

Follow the steps in the Using the code example section to run this code example.

Note: NetXDuo network stack used with ThreadX does not have the option to dynamically configure the TCP keep alive parameters (interval, count, and idle time). Therefore, the secure sockets cy_socket_setsockopt function fails with an error code "CY_RSLT_MODULE_SECURE_SOCKETS_OPTION_NOT_SUPPORTED".

In the code example, you can skip cy_socket_setsockopt calls (except CY_SOCKET_SO_TCP_KEEPALIVE_ENABLE) related to TCP keepalive in the ThreadX environment. And you can configure the desired TCP keep alive parameters by changing the following defines in nx_user.h file:

NX_TCP_KEEPALIVE_RETRIES
NX_TCP_KEEPALIVE_INITIAL
NX_TCP_KEEPALIVE_RETRY

Note: The version of the code example currently supports ThreadX and the NetXDuo network stack in GCC_ARM toolchain only. Support for other toolchains will be added in a future version of the code example.

Related resources

Resources	Links
Application notes	AN228571 – Getting started with PSoC™ 6 MCU on ModusToolbox™ software AN215656 – PSoC™ 6 MCU: Dual-CPU system design
Code examples	Using ModusToolbox™ software on GitHub
Device documentation	PSoC™ 6 MCU datasheets PSoC™ 6 technical reference manuals
Development kits	Select your kits from the evaluation board finder
Libraries on GitHub	mtb-pdl-cat1 – PSoC™ 6 Peripheral Driver Library (PDL) mtb-hal-cat1 – Hardware Abstraction Layer (HAL) library retarget-io – Utility library to retarget STDIO messages to a UART port
Middleware on GitHub	psoc6-middleware – Links to all PSoC™ 6 MCU middleware
Tools	Eclipse IDE for 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.

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.

For PSoC™ 6 MCU devices, see How to design with PSoC™ 6 MCU - KBA223067 in the Infineon Developer community.

Document history

Document title: CE229153 - TCP server

Version	Description of change
1.0.0	New code example.
1.1.0	Updated for ModusToolbox™ 2.1. Code updated to use Secure Sockets and Wi-Fi Connection Manager libraries.
1.2.0	Makefile updated to sync with BSP changes. Code updated to use RTOS Task Notification.
2.0.0	Major update to support ModusToolbox™ software v2.2, added support for new kits. Added soft AP Wi-Fi interface mode This version is not backward compatible with ModusToolbox™ software v2.1.
2.1.0	Added support for new kits
2.2.0	Updated to support FreeRTOS v10.3.1
3.0.0	Major update to support ModusToolbox™ v3.0 and BSPs v4.X. This version is not backward compatible with previous versions of ModusToolbox™
3.1.0	Added support for CY8CKIT-064B0S2-4343W
4.0.0	Updated to use abstraction-rtos to support various RTOS environments
4.1.0	Added support for CY8CEVAL-062S2-CYW43022CUB

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