IR Gesture Click

How does it work?

IR Gesture Click is based on the APDS-9960, digital proximity, ambient light, RGB, and gesture sensor from Avago Technologies. The sensor uses its IR LED and photodiodes to convert physical motion information into digital information. Besides different directions detection, the complex gesture sensing consists of ambient light rejection, offset compensation, a programmable driver for IR LED current, and 32 dataset storage FIFO. The infrared LED driver comes factory calibrated.

The proximity detection feature provides distance measurement (for example, a mobile device screen to the user’s ear) by photodiode detection of reflected IR energy (sourced by the integrated LED). Detect/release events are interrupted-driven and occur whenever proximity result crosses upper or lower threshold settings. The proximity engine features offset adjustment registers to compensate for system offset caused by unwanted IR energy reflections appearing at the sensor. The IR LED intensity is factory trimmed to eliminate the need for end-equipment calibration due to component variations. Proximity results are further improved by automatic ambient light subtraction.

The color and ALS detection feature provides red, green, blue, and clear light intensity data. Each R, G, B, and C channel has a UV and IR blocking filter and a dedicated data converter producing 16-bit data simultaneously. This architecture allows applications to accurately measure ambient light and sense color, which enables devices to calculate color temperature and control display backlight. The APDS-9960 has very high sensitivity and can be ideally suited for operation behind dark glass.

To communicate with the host MCU, this Click board™ uses an I2C interface over the mikroBUS™ socket, with data rates up to 400kHz. The interrupt signals of the APDS-9960 use the INT pin of the mikroBUS™ socket as an additional hardware feature. As this sensor can be used for developing hand-held battery-powered mobile devices, it should be said that power consumption can be further optimized with adjustable IR LED timing.

This Click board™ can only be operated with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used, as a reference, for further development.

Specifications

Pinout diagram

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

Notes	Pin					Pin	Notes
	NC	1	AN	PWM	16	NC
	NC	2	RST	INT	15	INT	Interrupt
	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	NC
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

IR Gesture Click electrical specifications

Software Support

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

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

Library Description

This library contains API for IR Gesture Click driver.

Key functions

• Function starts the gesture recognition engine on the APDS-9960 IC on IR Gesture Click.

• Function processes a gesture event and returns best guessed position engine on IR Gesture Click.

• Function compares input data and returns position of gesture

Example Description

This Click enables contactless gesture recognition: basic directional swipes (up, down, left or right).

 void application_task ( void ) 
 { 
     position = irgesture_detect_gesture( &irgesture ); 

     if ( position_old != position ) 
     { 
         if ( position == IRGESTURE_FAR ) 
         { 
             log_printf( &logger, "       F A R        rn" ); 
         } 
         if ( position == IRGESTURE_RIGHT ) 
         { 
             log_printf( &logger, "     R I G H T      rn" ); 
         } 
         if ( position == IRGESTURE_LEFT ) 
         { 
             log_printf( &logger, "      L E F T       rn" ); 
         } 
         if ( position == IRGESTURE_UP ) 
         { 
             log_printf( &logger, "        U P         rn" ); 
         } 
         if ( position == IRGESTURE_DOWN ) 
         { 
             log_printf( &logger, "      D O W N       rn" ); 
         } 
         if ( position == IRGESTURE_NEAR ) 
         { 
             log_printf( &logger, "      N E A R       rn" ); 
         } 

         position_old = position; 
         log_printf( &logger, "--------------------rn" ); 

         Delay_ms( 1000 ); 
     } 
 }

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

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.IrGesture

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 MIKROE compilers.

mikroSDK

This Click board™ is supported with mikroSDK – MIKROE Software Development Kit, that needs to be downloaded from the LibStock and installed for the compiler you are using to ensure proper operation of mikroSDK compliant Click board™ demo applications.

For more information about mikroSDK, visit the official page.