CapSense Click

How does it work?

CapSense Click is based on the CY8C201A0, a multi-channel capacitive touch sensor from Infineon Technologies. The CY8C201A0 takes human body capacitance as an input and directly provides real-time sensor information via a serial interface. The user can also configure registers with parameters needed to adjust the operation and sensitivity of the CapSense touch buttons and slider and permanently store the settings.

As mentioned earlier, this board contains a 5-segment capacitive sensing slider that can detect a slide in either the UP or DOWN direction, as well as two touch button pads which are the only elements on the top side of the board. Each of these touch button pads has a LED indicator representing the activity in that field. If a touch event is detected on one of these onboard pads, the state of the corresponding LED will be changed, indicating an activated channel; more precisely, touch has been detected on that specific field.

CapSense Click communicates with MCU using the standard I2C 2-Wire interface to read data and configure settings. The CY8C201A0 contains multiple operating modes: Active, Periodic Sleep, and Deep Sleep Mode, to meet different power consumption requirements. In the case of using some of the existing Sleep modes, the user is provided with the possibility of controlling these states via the GPO pin, routed to the AN pin of the mikroBUS™ socket, or this pin can be set in software as an interrupt pin indicating when a specific interrupt event occurs (touch detection). Besides, a Reset pin, routed to the RST pin of the mikroBUS™ socket, causes all operations of the CY8C201A0s CPU and blocks to stop and return to a pre-defined state.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the PWR SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to use the communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

Tutorials

Modern slider with Cap-sense - MikroElektronika Learn

Cap-sense or capacitive sensing is a measurement of changes in capacitance. The technology is based on capacitive coupling and can detect approaching or touching the sensor by any conductive object or object with a dielectric different from the surrounding air.

Specifications

Pinout diagram

This table shows how the pinout on CapSense Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
User-Configurable Pin	GPO	1	AN	PWM	16	NC
Reset	RST	2	RST	INT	15	NC
	NC	3	CS	RX	14	NC
	NC	4	SCK	TX	13	NC
	NC	5	MISO	SCL	12	SCL	I2C Clock
	NC	6	MOSI	SDA	11	SDA	I2C Data
Power Supply	3.3V	7	3.3V	5V	10	5V	Power Supply
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

CapSense Click electrical specifications

Software Support

We provide a library for the CapSense Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for CapSense Click driver.

Key functions

• This function gets slider level.

Example Description

This example waits user to press top and bottom button to turn click's LEDs ON or OFF.

 void application_task ( void ) 
 { 
     uint8_t current_led_state; 
     uint8_t button_select; 
     uint8_t slider_lvl; 
     char output_lvl[ 10 ]; 

     button_select = capsense_read_data( &capsense, CAPSENSE_CS_READ_STATUS0 ); 
     slider_lvl = capsense_get_slider_lvl( &capsense ); 
     capsense_write_data( &capsense, CAPSENSE_OUTPUT_PORT0, current_led_state ); 

     Delay_ms( 100 ); 

     if ( button_select == 8 ) 
     { 
         current_led_state ^= 0x01; 
         log_printf( &logger, "Toggle LED1rn"); 
         Delay_ms( 100 ); 
     } 
     if ( button_select == 16 ) 
     { 
         current_led_state ^= 0x02; 
         log_printf( &logger, "Toggle LED2rn"); 
         Delay_ms( 100 ); 
     } 
     if ( button_select == 24 ) 
     { 
         current_led_state = ~current_led_state; 
         log_printf( &logger, "Toggle both LEDsrn"); 
         Delay_ms( 100 ); 
     } 

     if ( slider_lvl != 0 ) 
     { 
         bits_to_str( slider_lvl, output_lvl ); 
         log_printf( &logger, "Slider level - channels [5-1]:t%s rn", &output_lvl[ 3 ] ); 
         Delay_ms( 100 ); 
     } 
 }

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.CapSense

Additional notes and informations

Depending on the development board you are using, you may need USB UART click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MikroElektronika compilers.

mikroSDK

This Click board™ is supported with mikroSDK - MikroElektronika Software Development Kit. To ensure proper operation of mikroSDK compliant Click board™ demo applications, mikroSDK should be downloaded from the LibStock and installed for the compiler you are using.

For more information about mikroSDK, visit the official page.