Enable secure and reliable data transfer over long distances with Ra-01S and ATmega324P
LoRa™ wireless radio-frequency module for ultra-long-distance spread-spectrum communication
Published Sep 04, 2024
Click board™
LR 6 Click
Dev. board
EasyAVR v7
Compiler
NECTO Studio
MCU
ATmega324P
Unlock ultra-long-range communication with the power of LoRa™ technology
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Hardware Overview
How does it work?
LR 6 Click is based on the Ra-01S, a LoRa™ wireless radio frequency module from Ai-Thinker Technology, designed for ultra-long-distance spread-spectrum communication. The Ra-01S module uses the SX1268 radio chip, primarily employing LoRa™ modulation technology for extended communication ranges. This module is known for its robust anti-interference capabilities and low current consumption, making it ideal for applications requiring reliable long-range communication. With Semtech's patented LoRa™ technology, the SX1268 chip offers exceptional sensitivity exceeding -148dBm and a power output of +22dBm. It supports multiple modulation methods, including FSK, GFSK, MSK, GMSK, LoRa™, and OOK, within the 433MHz frequency band (ranging from 410MHz to 525MHz).
Compared to traditional modulation technologies, LoRa™ offers significant advantages regarding anti-blocking and signal selection, addressing distance, interference, and power efficiency challenges. LR 6 Click is well-suited for various applications such as automatic meter reading, home and building automation, security systems, and remote irrigation systems, where long-distance communication and reliability are critical. This Click board™ communicates with the host MCU through a standard 4-wire SPI interface with frequencies up to 10MHz. In addition to the interface pins, the Ra-01S module uses the MD pin from the mikroBUS™ socket to select the TX or RX operational mode. It features a reset pin (RST) along with a RESET button for module resetting. This board also includes two unpopulated two-pin headers - one for
I/O digital signals for additional software configurations, another for an additional UART interface for RF port control, and a BSY pin alongside a red BUSY LED that indicates data transmission activity (module status). LR 6 Click also features the SMA antenna connector with an impedance of 50Ω, compatible with various antennas available from MIKROE, like the Rubber Antenna 433MHz, to enhance its connectivity. This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. Also, it comes equipped with a library containing functions and an example code that can be used as a reference for further development.
Features overview
Development board
EasyAVR v7 is the seventh generation of AVR development boards specially designed for the needs of rapid development of embedded applications. It supports a wide range of 16-bit AVR microcontrollers from Microchip and has a broad set of unique functions, such as a powerful onboard mikroProg programmer and In-Circuit debugger over USB. The development board is well organized and designed so that the end-user has all the necessary elements in one place, such as switches, buttons, indicators, connectors, and others. With four different connectors for each port, EasyAVR v7 allows you to connect accessory boards, sensors, and custom electronics more
efficiently than ever. Each part of the EasyAVR v7 development board contains the components necessary for the most efficient operation of the same board. An integrated mikroProg, a fast USB 2.0 programmer with mikroICD hardware In-Circuit Debugger, offers many valuable programming/debugging options and seamless integration with the Mikroe software environment. Besides it also includes a clean and regulated power supply block for the development board. It can use a wide range of external power sources, including an external 12V power supply, 7-12V AC or 9-15V DC via DC connector/screw terminals, and a power source via the USB Type-B (USB-B)
connector. Communication options such as USB-UART and RS-232 are also included, alongside the well-established mikroBUS™ standard, three display options (7-segment, graphical, and character-based LCD), and several different DIP sockets which cover a wide range of 16-bit AVR MCUs. EasyAVR v7 is an integral part of the Mikroe ecosystem for rapid development. Natively supported by Mikroe software tools, it covers many aspects of prototyping and development thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.
Microcontroller Overview
MCU Card / MCU
Architecture
AVR
MCU Memory (KB)
32
Silicon Vendor
Microchip
Pin count
40
RAM (Bytes)
2048
You complete me!
Accessories
Right angle 433MHz rubber antenna boasts a frequency range of 433MHz, ensuring optimal performance within this spectrum. With a 50Ohm impedance, it facilitates efficient signal transmission. The antenna's vertical polarization enhances signal reception in a specific orientation. Featuring a 1.5dB gain, it can improve signal strength to some extent. The antenna can handle a maximum input power of 50W, making it suitable for various applications. Its compact 50mm length minimizes spatial requirements. Equipped with an SMA male connector, it easily interfaces with compatible devices. This antenna is an adaptable solution for wireless communication needs, particularly when vertical polarization is crucial.
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 EasyAVR v7 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 LR 6 Click driver.
Key functions:
lr6_send_data- This function sends a desired number of data bytes to the buffer by using the selected mode using the SPI serial interface.lr6_receive_data- This function receives a desired number of data bytes to the buffer by using the SPI serial interface.lr6_set_lr_config- This function performs the desired LoRa configuration by using the SPI serial interface.
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 main.c
* @brief LR 6 Click example
*
* # Description
* This example demonstrates the use of LR 6 Click board by processing
* the incoming data and displaying them on the USB UART.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initialization of SPI module and log UART.
* After driver initialization, the app executes a default configuration.
*
* ## Application Task
* The demo application is an echo example that sends a demo LoRa packet string
* and receives and processes all incoming data.
* Results are being sent to the UART Terminal, where you can track their changes.
*
* @author Nenad Filipovic
*
*/
#include "board.h"
#include "log.h"
#include "lr6.h"
static lr6_t lr6;
static log_t logger;
// Demo string to be sent
#define LR6_DEMO_TEXT "MikroE\r\n"
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
lr6_cfg_t lr6_cfg; /**< Click config object. */
/**
* 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.
lr6_cfg_setup( &lr6_cfg );
LR6_MAP_MIKROBUS( lr6_cfg, MIKROBUS_1 );
if ( SPI_MASTER_ERROR == lr6_init( &lr6, &lr6_cfg ) )
{
log_error( &logger, " Communication init." );
for ( ; ; );
}
if ( LR6_ERROR == lr6_default_cfg ( &lr6 ) )
{
log_error( &logger, " Default configuration." );
for ( ; ; );
}
log_info( &logger, " Application Task " );
log_printf( &logger, " --------------------\r\n" );
}
void application_task ( void )
{
uint8_t rx_data[ 255 ] = { 0 };
if ( LR6_OK == lr6_send_data( &lr6, LR6_DEMO_TEXT, strlen( LR6_DEMO_TEXT ), LR6_TX_MODE_SYNC ) )
{
log_info( &logger, " Send - success" );
uint8_t rx_len = 0;
do
{
if ( LR6_OK == lr6_receive_data( &lr6, rx_data, strlen( LR6_DEMO_TEXT ), &rx_len ) )
{
if ( rx_len > 0 )
{
log_info( &logger, " Receive - success" );
log_printf( &logger, " > Receive: " );
for ( uint8_t cnt = 0; cnt < strlen( LR6_DEMO_TEXT ); cnt++ )
{
log_printf( &logger, "%c", rx_data[ cnt ] );
}
int8_t rssi, snr;
if ( LR6_OK == lr6_get_packet_status( &lr6, &rssi, &snr ) )
{
log_printf( &logger, " Rssi Pkt: %d dBm\r\n", ( int16_t ) rssi );
log_printf( &logger, " Snr Pkt : %d dB\r\n", ( int16_t ) snr );
log_printf( &logger, " --------------------\r\n" );
break;
}
}
}
}
while ( rx_len == 0 );
}
else
{
log_info( &logger, "Send - fail" );
}
Delay_ms ( 1000 );
}
int main ( void )
{
/* Do not remove this line or clock might not be set correctly. */
#ifdef PREINIT_SUPPORTED
preinit();
#endif
application_init( );
for ( ; ; )
{
application_task( );
}
return 0;
}
// ------------------------------------------------------------------------ END
