# Case 27: The Distance Indicator ## Introduction This is a distance detection device. In order to prevent the spread of the epidemic, people should maintain a certain social distance in public. This device can display the distance between the carrier and the person in front of it on the screen. ![](./images/case_27_01.png) ## Quick Start ### Materials Required Nezha expansion board × 1 micro:bit V2 × 1 sonar sensor × 1 Bricks × n ***Tips: You may need to purchase [Nezha Inventor's Kit](https://shop.elecfreaks.com/products/elecfreaks-micro-bit-nezha-48-in-1-inventors-kit-without-micro-bit-board?_pos=2&_sid=ed1b6fbd2&_ss=r) if you want all the above compoents.*** ### Connection Diagram Inset the micro:bit, and connect the sonar:bit to J1 port on Nezha expansion board. ![](./images/case_27_03.png) ### Assembly Video Video link: [https://youtu.be/0HgP_YVgNJU](https://youtu.be/0HgP_YVgNJU) ### Assembly Steps ![](./images/case_step_27_01.png) ![](./images/case_step_27_02.png) ![](./images/case_step_27_03.png) ![](./images/case_step_27_04.png) ![](./images/case_step_27_05.png) ## MakeCode Programming ### Step 1 Click "Advanced" in the MakeCode drawer to see more choices. ![](./images/case_01_10.png) We need to add a package for programming. Click "Extensions" in the bottom of the drawer and search with "nezha" to download it. ![](./images/case_03_09.png) ***Note:*** If you met a tip indicating the codebase might be deleted due to incompatibility, you may continue as the tips say or create a new project in the menu. ### Step 2 ### Programme as the pictures indicate ![](./images/case_27_10.png) ### Reference Link: [https://makecode.microbit.org/_Vb69KzLR3Dhe](https://makecode.microbit.org/_Vb69KzLR3Dhe) You may download it directly below:
### Result After powering on, the detected distance displays on the micro:bit. ![](./images/case-gif-27.gif)