Cypress PSoC 5 FIRSTTOUCH CY8CKIT-014, Руководство пользователя

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26 CY8CKIT-014 PSoC 5 FirstTouch Starter Kit Guide, Spec. # 001-57708 Rev. **
Example Projects
4.4 CapSense Slider
This project shows how to detect the position of a finger on the CapSense slider of the PSoC 5 First-
Touch Starter Kit board and indicate its position on the LED display.
Running the CapSense project:
1. Connect the PSoC 5 FirstTouch Starter Kit board to the USB port of the PC through the USB
cable.
2. Click on the example project CapSenseSlider from Kits and Solutions present on the Startup
page of the PSoC Creator.
3. Make a folder in the desired location and click OK .
4. Project opens up in PSoC Creator and gets saved in that folder.
5. Follow step 1 to 4 in section
4.1.3 Build, Program, and Run the PSoC Rocks Project on page 14
to program the project into the PSoC 5 FirstTouch Starter Kit board.
6. When the download is complete, remove the PSoC 5 FirstTouch Starter Kit board from the USB
port and connect a 9V DC battery to the battery connector of the PSoC 5 FirstTouch Starter Kit
board.
7. Move your finger along the CapSense Slider and see the corresponding LEDs light up.
4.4.1 How the CapSense Slider Project Works
Capacitive sensing determines the presence of a conductive element, such as the finger, on a
capacitive sensor incorporated on the PCB. The kit consists of a bank of CapSense sensors in the
form of a slider. The size of the sensors and their position is designed such that when a finger is
placed on any part of the slider, at least three sensors are active (it detects the presence of the finger
by a change in its capacitance value).
The CapSense component provides APIs, which report the centroid (relative position) of the finger
on the slider based on the active sensors. The firmware then lights up the LED corresponding to this
centroid position.