mikroe_stretch

Stretch Click (Mikroe)

Summary

This example project shows an example of Mikroe Stretch Click board driver integration with the Silicon Labs Platform.

Stretch Click is a compact add-on board for measuring stretch forces with conductive rubber cords. This board features circuitry that allows measuring the stretch forces of the 2mm diameter conductive rubber cord. This Click board™ comes equipped with the screw terminal, and two copper exposed pads, aside from the screw terminal, in addition to using the cord with alligator clamps.

Required Hardware

• EFR32xG24-EK2703A EFR32xG24 Explorer Kit

• Or SiWx917 Wi-Fi 6 and Bluetooth LE 8 MB Flash SoC Pro Kit (BRD4002 + BRD4338A)

• Mikroe Stretch Click

Hardware Connection

• If the EFR32xG24 Explorer Kit is used:

  The Stretch Click board supports MikroBus, so it can connect easily to Explorer Kit via MikroBus header. Assure that the board's 45-degree corner matches the Explorer Kit's 45-degree white line.

  The hardware connection is shown in the image below:

  

• If the SiWx917 Wi-Fi 6 and Bluetooth LE 8 MB Flash SoC Pro Kit is used:

  Description	BRD4338A GPIO	BRD4002 Breakout Pad	Stretch Click
  Positive analog input	ULP_GPIO_1	P16	OUT
  Negative analog input	ULP_GPIO_7	EXP_HEADER-15 to GND	--
  LED control	GPIO_46	P24	PWM

Setup

You can either create a project based on an example project or start with an empty example project.

1. From the Launcher Home, add your board to My Products, click on it, and click on the EXAMPLE PROJECTS & DEMOS tab. Find the example project filtering by stretch.

2. Click Create button on the Third Party Hardware Drivers - Stretch Click (Mikroe) example. Example project creation dialog pops up -> click Create and Finish and Project should be generated.

   

3. Build and flash this example to the board.

Start with an empty example project

1. Create an "Empty C Project" for the "EFR32xG24 Explorer Kit Board" using Simplicity Studio v5. Use the default project settings.

2. Copy the file app/example/mikroe_stretch/app.c into the project root folder (overwriting the existing file).

3. Install the software components:

   • Open the .slcp file in the project.

   • Select the SOFTWARE COMPONENTS tab.

   • Install the following components:

     If the EFR32xG24 Explorer Kit is used:

     • [Services] → [IO Stream] → [IO Stream: USART] → default instance name: vcom
     • [Application] → [Utility] → [Log]
     • [Services] → [Timers] → [Sleep Timer]
     • [Third Party Hardware Drivers] → [Sensors] → [Stretch Click (Mikroe)] → use the default configuration.

     If the SiWx917 Wi-Fi 6 and Bluetooth LE 8 MB Flash SoC Pro Kit is used:

     • [WiSeConnect 3 SDK] → [Device] → [Si91x] → [MCU] → [Service] → [Sleep Timer for Si91x]
     • [WiSeConnect 3 SDK] → [Device] → [Si91x] → [MCU] → [Peripheral] → [ADC] → [channel_1] → use default configuration
     • [Third Party Hardware Drivers] → [Sensors] → [Stretch Click (Mikroe)]

4. Build and flash this example to the board.

Note:

• Make sure that the Third Party Hardware Drivers extension is installed. If not, follow this documentation.

• SDK Extension must be enabled for the project to install the "Stretch Click (Mikroe)" component. Selecting this component will also include "IADC" component.

How It Works

Driver Layer Diagram

Software Component

Testing

This example reads the ADC value. With ADC value, you can get stretch of the cord.

After the sensor is initialed successfully, the application reads the analog signal every 500 milliseconds. Right after getting this value, it will be converted to a Decibel value.

To test the functionality, you can change the length of the Rubber Cord which be connected between two Alligator Clamps. The ADC value will be reduce when the length of the cord shorter and vice versa. If the ADC value lower than 500 (you can change this value on file app/example/mikroe_stretch/app.c), LED on Stretch click board will be turn on. Then you will see the ADC value change on the console in Simplicity Studio or other third-party terminal tools. A screenshot of the console output is shown in the figure below.

Report Bugs & Get Support

To report bugs in the Application Examples projects, please create a new "Issue" in the "Issues" section of third_party_hw_drivers_extension repo. Please reference the board, project, and source files associated with the bug, and reference line numbers. If you are proposing a fix, also include information on the proposed fix. Since these examples are provided as-is, there is no guarantee that these examples will be updated to fix these issues.

Questions and comments related to these examples should be made by creating a new "Issue" in the "Issues" section of third_party_hw_drivers_extension repo.