Getting Started with the FRDM-K22F

Find out more.

• True debug support via SWD and JTAG
• High software flexibility
• Full set of peripheral drivers with source
• Application examples and project files

Find out more .

• Online compiler, no SWD or JTAG debug
• Simple, heavily abstracted programming interface
• Useful but limited drivers with source
• Community-submitted examples

Import the MCUXpresso SDK

1. Open up the MCUXpresso IDE
2. Switch to the Installed SDKs view within the MCUXpresso IDE window
3. Open Windows Explorer, and drag and drop the FRDM-K22F SDK (unzipped) file into the "Installed SDKs" view
4. You will get the following pop-up. Click "OK" to continue the import:
5. The installed SDK will appear in the Installed SDKs view as shown below:

Build an Example Application

The following steps will guide you through opening the hello_world example.

1. Find the Quickstart Panel in the lower left hand corner
2. Then click on Import SDK examples(s)
3. Click on the frdmk22f board to select that you want to import an example that can run on that board, and then click Next
4. Use the arrow button to expand the "demo_apps" category, and then click the checkbox next to 'hello_world' to select that project. To use the UART for printing (instead of the default semihosting), clear the "Enable semihost" checkbox under the project options. Then, click "Next"
5. Now, build the project by clicking on the project name and then click on the Build icon
6. You can see the status of the build in the Console tab

Run an Example Application

1. Now that the project has been compiled, you can now flash it to the board and run it
2. Make sure the FRDM-K22F board is plugged in, and click on "Debug" in the Quickstart Panel
3. MCUXpresso IDE will probe for connected boards and should find the MBED CMSIS-DAP debug probe that is part of the integrated OpenSDA circuit on the FRDM-K22F. Click OK to continue
4. The firmware will be downloaded to the board and the debugger will be started
5. Open up a terminal program and connect it to the COM port the board enumerated as. Use 115,200 baud rate, 8 data bits, no parity and 1 stop bit
6. Start the application by clicking the "Resume" button:
7. The hello_world application is now running and a banner is displayed on the terminal. If this is not the case, check your terminal settings and connections
8. Use the controls in the menu bar to pause, step into, and step over instructions, and then stop the debugging session by click on the Terminate icon:

Build an Example Application

The following steps will guide you through opening the hello_world application. These steps may change slightly for other example applications as some of these applications may have additional layers of folders in their path.

1. If not already done, open the desired example application workspace. Most example application workspace files can be located using the following path:

   <install_dir>/boards/<sdk_board_name>/<example_type>/<application_name>/iar

   Using the hello_world demo as an example, the path is:

   <install_dir>/boards/frdmk22f/demo_apps/hello_world/iar

2. Select the desired build target from the drop-down. For this example, select the "hello_world - Debug" target
3. To build the application, click the "Make" button, highlighted in red below
4. The build will complete without errors

Run an Example Application

The FRDM-K22F board comes loaded with the mbed/CMSIS-DAP debug interface from the factory. If you have changed the debug OpenSDA application on your board, visit OpenSDA for information on updating or restoring your board to the factory state.

1. Connect the development platform to your PC via USB cable between the "SDAUSB" USB port on the board and the PC USB connector
2. Open the terminal application on the PC (such as PuTTY or Tera Term) and connect to the debug COM port you determined earlier. Configure the terminal with these settings:
   • 115,200 baud rate
   • No parity
   • 8 data bits
   • 1 stop bit
3. Click the "Download and Debug" button to download the application to the target
4. The application is then downloaded to the target and automatically runs to the main() function
5. Run the code by clicking the "Go" button to start the application
6. The hello_world application is now running and a banner is displayed on the terminal. If this is not the case, check your terminal settings and connections

Install CMSIS device pack

After the MDK tools are installed, Keil device packs must be installed to fully support the device from a debug perspective. These packs include things such as memory map information, register definitions and flash programming algorithms. Follow these steps to install the appropriate CMSIS pack.

1. Open the MDK IDE, which is called µVision. In the IDE, select the "Pack Installer" icon
2. In the Pack Installer window, search for 'k22' to bring up the K22F family. Click on the MK22FN1M0xxx10 name, and then in the right hand side you'll see the Keil::Kinetis_K20_DFP pack. Click on the "Install" button next to the pack. This process requires an internet connection to successfully complete
3. After the installation finishes, close the Pack Installer window and return to the µVision IDE

Build the Example Application

The following steps will guide you through opening the hello_world application. These steps may change slightly for other example applications as some of these applications may have additional layers of folders in their path.

1. If not already done, open the desired demo application workspace in:

   <install_dir>/boards/<sdk_board_name>/<example_type>/<application_name>/mdk

   The workspace file is named <application_name>.uvmpw, so for this specific example, the actual path is:

   <install_dir>/boards/frdmk22f/demo_apps/hello_world/iar/hello_world.uvmpw

2. To build the demo project, select the "Rebuild" button, highlighted in red
3. The build will complete without errors

Run an Example Application

The FRDM-K22F board comes loaded with the mbed/CMSIS-DAP debug interface from the factory. If you have changed the debug OpenSDA application on your board, visit OpenSDA for information on updating or restoring your board to the factory state.

1. Connect the development platform to your PC via USB cable between the "SDAUSB" USB port on the board and the PC USB connector
2. Open the terminal application on the PC (such as PuTTY or Tera Term) and connect to the debug COM port you determined earlier. Configure the terminal with these settings:
   • 115,200 baud rate
   • No parity
   • 8 data bits
   • 1 stop bit
3. After the application is properly built, click the "Download" button to download the application to the target
4. Run the code by clicking the "Run" button to start the application
5. The hello_world application is now running and a banner is displayed on the terminal. If this is not the case, check your terminal settings and connections

Set Up Toolchain

This section contains the steps to install the necessary components required to build and run a KSDK demo application with the Arm GCC toolchain, as supported by the MCUXpresso SDK. There are many ways to use Arm GCC tools, but this example focuses on a Windows environment. Though not discussed here, GCC tools can also be used with both Linux OS and Mac OSX.

Install GCC Arm Embedded Toolchain

Download and run the installer from GNU Arm Embedded Toolchain . This is the actual toolchain (i.e., compiler, linker, etc). The GCC toolchain should correspond to the latest supported version, as described in the Kinetis SDK Release Notes.

Install MinGW

The Minimalist GNU for Windows (MinGW) development tools provide a set of tools that are not dependent on third party C-Runtime DLLs (such as Cygwin). The build environment used by the KSDK does not utilize the MinGW build tools, but does leverage the base install of both MinGW and MSYS. MSYS provides a basic shell with a Unix-like interface and tools.

1. Download the latest MinGW mingw-get-setup installer from MinGW - Minimalist GNU for Windows Files

2. Run the installer. The recommended installation path is C:\MinGW, however, you may install to any location

Note: The installation path cannot contain any spaces.

3. Ensure that the "mingw32-base" and "msys-base" are selected under Basic Setup
4. Click "Apply Changes" in the "Installation" menu and follow the remaining instructions to complete the installation

5. Add the appropriate item to the Windows operating system Path environment variable. It can be found under "Control Panel → System and Security → System → Advanced System Settings in the "Environment Variables..." section. The path is:

   <mingw_install_dir>\bin

   Assuming the default installation path, C:\MinGW, an example is shown below. If the path is not set correctly, the toolchain does not work

   Note: If you have "C:\MinGW\msys\x.x\bin" in your PATH variable (as required by KSDK 1.0.0), remove it to ensure that the new GCC build system works correctly.

   

Add a New Environment Variable for ARMGCC_DIR

1. Create a new 'system' environment variable and name it ARMGCC_DIR. The value of this variable should point to the Arm GCC Embedded Toolchain installation path, which, for this example, is:

   C:\Program Files (x86)\GNU Tools Arm Embedded\7-2018-q2-update 7 2018

   Reference the installation folder of the GNU Arm GCC Embedded tools for the exact pathname of your installation

Install CMake

1. Download CMake 3.0.x from CMake
2. Install CMake, ensuring that the option "Add CMake to system PATH" is selected when installing. It's up to the user to select whether it's installed into the PATH for all users or just the current user. In this example, the assumption is that it's installed for all users
3. Follow the remaining instructions of the installer
4. You may need to reboot your system for the PATH changes to take effect

Build an Example Application

To build an example application, follow these steps.

1. If not already running, open a GCC Arm Embedded Toolchain command window. To launch the window, from the Windows operating system Start menu, go to "Programs → GNU Tools Arm Embedded <version>" and select "GCC Command Prompt"

2. Change the directory to the example application project directory, which has a path like this:

   <install_dir>/boards/<board_name>/<example_type>/<application_name>/armgcc

   For this guide, the exact path is:

   <install_dir>/boards/frdmk22f/demo_apps/hello_world/armgcc

3. Type "build_debug.bat" on the command line or double click on the "build_debug.bat" file in Windows operating system Explorer to perform the build. The output is shown in this figure:

Run an Example Application

The GCC tools require a J-Link debug interface. To update the OpenSDA firmware on your board to the latest J-Link app, visit OpenSDA. After installing the J-Link OpenSDA application, download the J-Link driver and software package from Segger Downloads .

1. Connect the development platform to your PC via USB cable between the "SDAUSB" USB port on the board and the PC USB connector
2. Open the terminal application on the PC (such as PuTTY or Tera Term) and connect to the debug COM port you determined earlier. Configure the terminal with these settings:
   • 115,200 baud rate
   • No parity
   • 8 data bits
   • 1 stop bit
3. Open the J-Link GDB Server application. Assuming the J-Link software is installed, the application can be launched by going to the Windows operating system Start menu and selecting "Programs → SEGGER → J-Link <version> J-Link GDB Server"
4. Modify the settings as shown below. The target device selection chosen for this example is the "MK22FM512xxx12" and use the SWD interface
5. After it is connected, the screen should resemble this figure:
6. If not already running, open a GCC Arm Embedded Toolchain command window. To launch the window, from the Windows operating system Start menu, go to "Programs → GNU Tools Arm Embedded <version>" and select "GCC Command Prompt"

7. Change to the directory that contains the demo application output. The output can be found in one of these paths, depending on the build target selected:

   <install_dir>/boards/<board_name>/<example_type>/<application_name>/armgcc/debug

   <install_dir>/boards/<board_name>/<example_type>/<application_name>/armgcc/release

   For this guide, the path is:

   <install_dir>/boards/frdmk22f/demo_apps/hello_world/armgcc/debug

8. Run the command "arm-none-eabi-gdb.exe <demo_name>.elf". For this example, it is "arm-none-eabi-gdb.exe hello_world.elf"
9. Run these commands:
   • target remote localhost:2331
   • monitor reset
   • monitor halt
   • load
   • monitor reset
10. The application is now downloaded and halted at the reset vector. Execute the "monitor go" command to start the example application
11. The hello_world application is now running and a banner is displayed in the terminal window

1. Open the MCUXpresso IDE
2. Click Import SDK Example(s) from the QuickStart Panel
3. Click on the frdmk22f board to select that you want to import an example that can run on that board, and then click Next
4. Type 'led' into the search bar, and select the "gpio_led_output" project under the gpio driver example. This particular project doesn't make use of UART, but for projects that do, make sure to select the "UART" option for the "SDK Debug Console". Then, click on "Finish"
5. Click on the "frdmk22f_gpio_led_output" project in the Project Explorer View and build, compile and run the demo as described previously
6. You should see a red LED blinking on the board
7. Terminate the debug session

1. Open the MCUXpresso Config Tools
2. In the wizard that comes up, browse to the place where the MCUXpresso SDK was unzipped, and then select the "Clone SDK example and create a new configuration" radio button and click Next
3. On the next screen, select the location of the MCUXpresso SDK that you had unzipped earlier. Then select the IDE that is being used
4. Select the project to clone. For this example, we want to use the LED project. You can filter for this by typing 'led' in the filter box and then selecting the "gpio_led_output" project. You can then also specify where to clone the project. Then, click on Finish
5. After cloning, go to the directory you selected and open up the project for your IDE. Import, compile and run the project as done in previous sections
6. You should see a red LED blinking on the board
7. Terminate the debug session
8. Go back to the MCUXpresso Config Tools program and continue on with the next section to learn how to use the Pins Tool

Note: Previously, you had to clone an SDK project like in the previous step.

Open Pins Tool in MCUXpresso IDE

1. Open the pins tool by right clicking on the "frdmk22f_gpio_led_output" project, and selecting "MCUXpresso Config Tools" and then "Open Pins"

Open Pins Tool in MCUXpresso Config Tools

1. Open the MCUXpresso Config Tools
2. In the wizard that comes up, select the "Open existing configuration" radio button, then select the project that you had clone and click Next

3. Open the Pins Tool by selecting Tools → Pins from the toolbar

Use the Pins Tool

1. The Pins Tool should now display the pin configuration for the led_output project
2. In the Pins view, look at the Routed Pins box to see all the routed pins for the project. You can see the peripheral the pin is associated with and the signal name, and the pin options
3. In the current configuration, PTA1 is routed as a GPIO to toggle the red LED. For this example, we'll use PTD5 instead to drive the blue LED
4. In the Pins screen, scroll down until you see PTA1. Click the checkbox next to it to unselect it
5. You'll see the following dialog box come up. Click next to PTA1 to unselect it and then click on Done
6. Search for PTD5, and click on the checkbox next to PTD5 to use that pin and select the PTD5 GPIO pin
7. PTD5 already has a defined identifier (i.e. LED_BLUE) set up for the FRDM-K22F for the led_output example configuration. Let's change the identifier to "My_LED" next to PTD5 in the Pins table
8. Now, it's time to implement these changes into the GPIO project by exporting the new updated pin_mux.c and pin_mux.h files that are generated by the Pins Tool. Click on Update Project in the menu bar
9. The screen that pops up will show the files that are changing and you can click on 'diff' to see the difference between the current file and the new file generated by the Pins Tool. Click on "OK" to overwrite the new files into your project

Note: The clocks and peripherals files may also be tagged as being updated since the header has been changed.


10. Now, inside the IDE, open up the gpio_led_ouput.c file
11. Change two #defines to tell the GPIO project to use the new PTD5 pin. Use the #defines that are found in pin_mux.h where were created by the Pins Tool

#define BOARD_LED_GPIO BOARD_INITPINS_MY_LED_GPIO
#define BOARD_LED_GPIO_PIN BOARD_INITPINS_MY_LED_PIN


12. Now, build and run the project as before. You will now see the blue LED blink!

Note: Previously, you had to clone an SDK project like in the previous steps.

Open Clocks Tool in MCUXpresso IDE

1. Open the Clocks Tool by right clicking on the "frdmk22f_gpio_led_output" project and selecting "MCUXpresso Config Tools" and then "Open Clocks"

Open Clocks Tool in MCUXpresso Config Tools

1. Open the MCUXpresso Config Tools
2. In the wizard that comes up, select the "Open existing configuration" radio button, then select the project that you had clone and click Next

3. Open the Clocks Tool by selecting Tools → Clocks from the toolbar

Use the Clocks Tool

1. The clock configuration for the "led_output" project will appear in the Clocks Tool:
2. Switch to the Clocks Diagram view, by clicking the tab in the upper left corner
3. Change the core clock frequency by clicking in the "Core Clock" field and typing '12'. You'll see all the other clock values automatically change as well to adjust to this slower speed. It will look like this when done:
4. Now, it's time to implement these changes into the GPIO project by exporting the new updated clock_config.c and clock_config.h files that are generated by the Clocks Tool. Click on Update Project in the menu bar
5. The screen that pops up will show the files that are changing and you can click on 'diff' to see the difference between the current file and the new file generated by the Clocks Tool. Click on "OK" to overwrite the new files into your project

Note: The pins and peripherals files may also be tagged as being updated since the header has been changed.


6. Now, open the led project in your IDE, and build, download and run the project as you did before
7. The blue LED should now be blinking at a much slower rate!