30 min

Bring a new level of precision and adaptability to lighting control with APDS-9160-003 and PIC18F25K40

Light's silent storytellers: The world of ambient sensors

Ambient 9 Click with Curiosity HPC

Published Jan 23, 2024

Click board™

Ambient 9 Click

Development board

Curiosity HPC


NECTO Studio



Discover how ambient light sensing solutions are reshaping the way we interact with light, delivering a brighter, smarter, and more efficient future



Hardware Overview

How does it work?

Ambient 9 Click is based on the APDS-9160-003, digital proximity, and ambient light sensing sensor from Broadcom Limited. The ambient light sensor provides a photopic response to light intensity in low light conditions or behind a darkened glass. It approximates the human eye's response, providing a direct readout where the output count is proportional to the ambient light level. The proximity detection also operates well from bright sunlight to dark rooms. Additionally, the device can be put into a low-power standby mode, providing a low average power consumption. The included IR LED can be pulsed in a proximity sensing system with more than 100 mA of rapidly switching current. The number of LED pulses can be configured by using the pulse step, and the

LED modulation frequency can be set from 60kHz to 100kHz in 5 steps. Proximity sensing resolution can vary from 8 to 11 bits, and the measurement rate can vary from 6.25 ms to 400 ms. This Click board™ is easy to program and read data because it does not require an overly demanding configuration. To read ambient or proximity data, it is only necessary to enable certain registers, which can also be seen in an example code that contains easy-to-use functions that may be used as a reference for further development. Ambient 9 Click communicates with the MCU using the standard I2C 2-wire interface. Standard (100 kHz) and Fast (400 kHz) I2C communication modes are available with the device. The I2C bus lines are routed to the dual bidirectional PCA9306

voltage-level translator from Texas Instruments, allowing interfacing with 3.3V and 5V MCUs. It also generates flexible ambient and proximity programmable interrupt signals routed on the INT pin of the mikroBUS™, which are triggered if upper or lower threshold values are crossed. It is also possible to deactivate a sensor after a certain interrupt event occurs. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. Also, this 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.

Ambient 9 Click top side image
Ambient 9 Click bottom side image

Features overview

Development board

Curiosity HPC, standing for Curiosity High Pin Count (HPC) development board, supports 28- and 40-pin 8-bit PIC MCUs specially designed by Microchip for the needs of rapid development of embedded applications. This board has two unique PDIP sockets, surrounded by dual-row expansion headers, allowing connectivity to all pins on the populated PIC MCUs. It also contains a powerful onboard PICkit™ (PKOB), eliminating the need for an external programming/debugging tool, two mikroBUS™ sockets for Click board™ connectivity, a USB connector, a set of indicator LEDs, push button switches and a variable potentiometer. All

these features allow you to combine the strength of Microchip and Mikroe and create custom electronic solutions more efficiently than ever. Each part of the Curiosity HPC development board contains the components necessary for the most efficient operation of the same board. An integrated onboard PICkit™ (PKOB) allows low-voltage programming and in-circuit debugging for all supported devices. When used with the MPLAB® X Integrated Development Environment (IDE, version 3.0 or higher) or MPLAB® Xpress IDE, in-circuit debugging allows users to run, modify, and troubleshoot their custom software and hardware

quickly without the need for additional debugging tools. Besides, it includes a clean and regulated power supply block for the development board via the USB Micro-B connector, alongside all communication methods that mikroBUS™ itself supports. Curiosity HPC development board allows you to create a new application in just a few steps. Natively supported by Microchip software tools, it covers many aspects of prototyping thanks to many number of different Click boards™ (over a thousand boards), the number of which is growing daily.

Curiosity HPC double image

Microcontroller Overview

MCU Card / MCU




MCU Memory (KB)


Silicon Vendor


Pin count


RAM (Bytes)


Used MCU Pins

mikroBUS™ mapper

Power Supply
I2C Clock
I2C Data
Power Supply

Take a closer look


Ambient 9 Click Schematic schematic

Step by step

Project assembly

Curiosity HPC front no-mcu image hardware assembly

Start by selecting your development board and Click board™. Begin with the Curiosity HPC as your development board.

Curiosity HPC front no-mcu image hardware assembly
IR Sense 4 Click front image hardware assembly
MCU DIP 28 hardware assembly
Prog-cut hardware assembly
Curiosity HPC 28pin-DIP - upright/background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
Necto image step 5 hardware assembly
Necto image step 6 hardware assembly
Necto DIP image step 7 hardware assembly
Necto No Display image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Debug Image Necto Step hardware assembly

Track your results in real time

Application Output

After loading the code example, pressing the "DEBUG" button builds and programs it on the selected setup.

Application Output Step 1

After programming is completed, a header with buttons for various actions available in the IDE appears. By clicking the green "PLAY "button, we start reading the results achieved with Click board™.

Application Output Step 3

Upon completion of programming, the Application Output tab is automatically opened, where the achieved result can be read. In case of an inability to perform the Debug function, check if a proper connection between the MCU used by the setup and the CODEGRIP programmer has been established. A detailed explanation of the CODEGRIP-board connection can be found in the CODEGRIP User Manual. Please find it in the RESOURCES section.

Application Output Step 4

Software Support

Library Description

This library contains API for Ambient 9 Click driver.

Key functions:

  • ambient9_als_data - Generic function for reading ALS data from sensor

  • ambient9_proxy_data - Generic function for reading proximity data from sensor

  • ambient9_enable_data - Function for enabeling sensor for ALS or proximity

Open Source

Code example

This example can be found in NECTO Studio. Feel free to download the code, or you can copy the code below.

 * \file 
 * \brief Ambient9 Click example
 * # Description
 * This example demonstrates the use of Ambient 9 Click board.
 * The demo application is composed of two sections :
 * ## Application Init 
 * Initializes the driver then reads the device status and part ID. If there's any error occured 
 * it displays an appropriate message on the USB UART. After that, it enables the device mode
 * defined by the dev_mode variable. ALS mode is selected by default.
 * ## Application Task  
 * Depending on the selected device mode, it reads an ambient light sensor or proximity data and 
 * displays the results on the USB UART every 100ms.
 * \author MikroE Team
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "ambient9.h"

// ------------------------------------------------------------------ VARIABLES

static ambient9_t ambient9;
static log_t logger;

static uint8_t dev_mode = 0;

// ------------------------------------------------------ APPLICATION FUNCTIONS

void application_init ( void )
    log_cfg_t log_cfg;
    ambient9_cfg_t cfg;

    uint8_t status_data;

     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, "---- Application Init ----" );

    //  Click initialization.

    ambient9_cfg_setup( &cfg );
    ambient9_init( &ambient9, &cfg );

    ambient9_generic_read( &ambient9, AMBIENT9_REG_PART_ID, &status_data, 1 );
    if ( AMBIENT9_PART_ID_VAL != status_data )
        log_printf( &logger, " *****  ERROR ID!  ***** \r\n" );
        for( ; ; );
    Delay_ms( 500 );
    ambient9_generic_read( &ambient9, AMBIENT9_REG_MAIN_STATUS, &status_data, 1 );
    if ( AMBIENT9_POWER_ON == ( status_data & AMBIENT9_POWER_ON ) )
        log_printf( &logger, " *****  ERROR POWER ON!  ***** \r\n" );
        for( ; ; );
    dev_mode = AMBIENT9_ALS;
    ambient9_enable_data( &ambient9, dev_mode );  

    log_printf( &logger, " ***** APP TASK ***** \r\n" );
    Delay_ms( 500 );

void application_task ( void )
    uint16_t proxy_data;
    uint32_t als_data;

    if ( AMBIENT9_ALS == dev_mode )
        als_data = ambient9_als_data( &ambient9 );
        log_printf( &logger, " - ALS data: %lu \r\n", als_data );
    else if ( AMBIENT9_PROXY == dev_mode )
        proxy_data = ambient9_proxy_data( &ambient9 );
        log_printf( &logger, " - Proximity data: %u \r\n", proxy_data );
    Delay_ms( 100 );

void main ( void )
    application_init( );

    for ( ; ; )
        application_task( );

// ------------------------------------------------------------------------ END

Additional Support