Experience the future of smart agriculture with MIC1557 and PIC18F57Q43
Unearth growth secrets through capacitive moisture mastery!
Published Feb 13, 2024
Click board™
Hydro Probe Click
Dev. board
Curiosity Nano with PIC18F57Q43
Compiler
NECTO Studio
MCU
PIC18F57Q43
From sustainable gardening to precision farming, our capacitive soil moisture sensing solution offers unparalleled accuracy, helping you make informed decisions by monitoring volumetric water content in the soil
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Hardware Overview
How does it work?
Hydro Probe Click uses the capacitive soil moisture sensor based on capacitive changes that are used to detect the volumetric water content of the soil. It based its operation on capacitive measurement, which has a great advantage over resistive measurement. Compared with resistive soil moisture sensors, capacitive sensors do not require direct exposure to the metal electrodes, which can significantly reduce the erosion of the electrodes. This Click board™ can only qualitatively test the humidity of the soil and can’t measure quantitatively. When the humidity of the soil rises, the output value decreases; conversely, when the humidity decreases, the output value becomes higher. It operates with a flexible power
supply voltage range, making it suitable for 3.3V and 5V MCUs. Hydro Probe Click functions as a capacitive soil moisture sensor using two main components, CMOS RC oscillator MIC1557 and 12-bit A/D converter MCP3221 with I2C serial interface. The oscillator frequency is set to 600kHz. From the oscillator, a signal goes to the soil moisture probe through a 10k resistor; these two elements act as a low-pass filter for the oscillator signal. The output analog signal from the capacitive probe goes through a diode to the MCP3221, A/D converter with 12-bit resolution, which converts that data and sends it to MCU. Communication to the MCP3221 is performed using a 2-wire I2C serial interface with available standard (100 kHz) or fast
(400 kHz) modes. To ensure you received the correct data, the Hydro Probe Click must be calibrated. The final output value is affected by probe insertion depth and how tight the soil packed around it is. It‘s recommended that the probe should not be placed on the depth which crosses the limit line on the Click board. 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.
Features overview
Development board
PIC18F57Q43 Curiosity Nano evaluation kit is a cutting-edge hardware platform designed to evaluate microcontrollers within the PIC18-Q43 family. Central to its design is the inclusion of the powerful PIC18F57Q43 microcontroller (MCU), offering advanced functionalities and robust performance. Key features of this evaluation kit include a yellow user LED and a responsive
mechanical user switch, providing seamless interaction and testing. The provision for a 32.768kHz crystal footprint ensures precision timing capabilities. With an onboard debugger boasting a green power and status LED, programming and debugging become intuitive and efficient. Further enhancing its utility is the Virtual serial port (CDC) and a debug GPIO channel (DGI
GPIO), offering extensive connectivity options. Powered via USB, this kit boasts an adjustable target voltage feature facilitated by the MIC5353 LDO regulator, ensuring stable operation with an output voltage ranging from 1.8V to 5.1V, with a maximum output current of 500mA, subject to ambient temperature and voltage constraints.
Microcontroller Overview
MCU Card / MCU
Architecture
PIC
MCU Memory (KB)
128
Silicon Vendor
Microchip
Pin count
48
RAM (Bytes)
8196
You complete me!
Accessories
Curiosity Nano Base for Click boards is a versatile hardware extension platform created to streamline the integration between Curiosity Nano kits and extension boards, tailored explicitly for the mikroBUS™-standardized Click boards and Xplained Pro extension boards. This innovative base board (shield) offers seamless connectivity and expansion possibilities, simplifying experimentation and development. Key features include USB power compatibility from the Curiosity Nano kit, alongside an alternative external power input option for enhanced flexibility. The onboard Li-Ion/LiPo charger and management circuit ensure smooth operation for battery-powered applications, simplifying usage and management. Moreover, the base incorporates a fixed 3.3V PSU dedicated to target and mikroBUS™ power rails, alongside a fixed 5.0V boost converter catering to 5V power rails of mikroBUS™ sockets, providing stable power delivery for various connected devices.
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Click board™ Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Curiosity Nano with PIC18F57Q43 as your development board.
Track your results in real time
Application Output
1. Application Output - In Debug mode, the 'Application Output' window enables real-time data monitoring, offering direct insight into execution results. Ensure proper data display by configuring the environment correctly using the provided tutorial.
2. UART Terminal - Use the UART Terminal to monitor data transmission via a USB to UART converter, allowing direct communication between the Click board™ and your development system. Configure the baud rate and other serial settings according to your project's requirements to ensure proper functionality. For step-by-step setup instructions, refer to the provided tutorial.
3. Plot Output - The Plot feature offers a powerful way to visualize real-time sensor data, enabling trend analysis, debugging, and comparison of multiple data points. To set it up correctly, follow the provided tutorial, which includes a step-by-step example of using the Plot feature to display Click board™ readings. To use the Plot feature in your code, use the function: plot(*insert_graph_name*, variable_name);. This is a general format, and it is up to the user to replace 'insert_graph_name' with the actual graph name and 'variable_name' with the parameter to be displayed.
Software Support
Library Description
This library contains API for Hydro Probe Click driver.
Key functions:
hydroprobe_avg_val- Get average value functionhydroprobe_min_val- Get minimum value functionhydroprobe_rel_env_hum- Get Relative humidity of the environment function
Open Source
Code example
The complete application code and a ready-to-use project are available through the NECTO Studio Package Manager for direct installation in the NECTO Studio. The application code can also be found on the MIKROE GitHub account.
/*!
* \file
* \brief HydroProbe Click example
*
* # Description
* This demo application measures moisture.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initalizes I2C driver, prerforms calibration and makes an initial log.
*
* ## Application Task
* This example shows the capabilities of the Hydro Probe click by measuring
* environment moisture content and displaying it in percent via USB UART.
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "hydroprobe.h"
// ------------------------------------------------------------------ VARIABLES
static hydroprobe_t hydroprobe;
static log_t logger;
static uint8_t humy_val = 0;
static uint16_t dry_val = 0;
static uint16_t wet_val = 0;
// ------------------------------------------------------- ADDITIONAL FUNCTIONS
void hydroprobe_calib ( )
{
uint8_t cnt;
log_printf( &logger, " Keep the Probe dry \r\n" );
dry_val = hydroprobe_max_val( &hydroprobe );
Delay_ms( 5000 );
log_printf( &logger, " Submerge the Probe in liquid \r\n" );
for ( cnt = 5; cnt > 0; cnt-- )
{
log_printf( &logger, " %d \r\n ", ( uint16_t ) cnt );
Delay_ms( 1000 );
}
log_printf( &logger, " Keep the Probe submerged \r\n" );
Delay_ms( 100 );
wet_val = hydroprobe_min_val( &hydroprobe );
log_printf( &logger, "--------------------\r\n" );
Delay_ms( 5000 );
}
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
hydroprobe_cfg_t cfg;
/**
* 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.
hydroprobe_cfg_setup( &cfg );
HYDROPROBE_MAP_MIKROBUS( cfg, MIKROBUS_1 );
hydroprobe_init( &hydroprobe, &cfg );
Delay_ms( 100 );
log_printf( &logger, "---------------------\r\n" );
log_printf( &logger, " Hydro Probe click \r\n" );
log_printf( &logger, "---------------------\r\n" );
hydroprobe_calib( );
log_printf( &logger, " Calibrated \r\n" );
log_printf( &logger, "---------------------\r\n" );
Delay_ms( 3000 );
}
void application_task ( void )
{
humy_val = hydroprobe_rel_env_hum( &hydroprobe, dry_val, wet_val );
log_printf( &logger, "Environment moisture content: %d %% \r\n ", ( uint16_t ) humy_val );
log_printf( &logger, "------------------------------\r\n" );
Delay_ms( 1000 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
Additional Support
Resources
Category:Environmental
