Remotely monitor and collect data from various types of consumption meters with TSS721A and STM32G474RE
Elevate your remote meter reading game
Published Nov 08, 2024
Click board™
M-Bus Slave Click
Dev. board
Nucleo 64 with STM32G474RE MCU
Compiler
NECTO Studio
MCU
STM32G474RE
This advanced solution, featuring the TSS721A transceiver, is designed to seamlessly integrate into Meter-Bus applications, adhering to EN1434-3 standards, and ensuring the highest level of performance and compatibility
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Hardware Overview
How does it work?
M-Bus Slave Click is based on the TSS721A, a single-chip transceiver developed for Meter-Bus standard (EN1434-3) applications from Texas Instruments. The connection to the bus is polarity independent and serves as a slave node in the system. M-Bus Slave Click has full galvanic isolation with optocouplers to improve the reliability of the whole circuit. The circuit is supplied by the master via the bus. The benefit of the TSS721A in M-Bus slaves is the reduction of the number of components needed, and therefore the cost of slaves. Apart from the transmission and reception of data by the M-Bus specification, this IC also provides translation from and to the operating voltage of the microprocessor to which it is connected, to be able to communicate with it. The communication can take place at baudrates
from 300 to 9600 Baud. Additional features include integrated protection against reversed polarity, a constant 3.3V power supply for the microprocessor, and the prompt indication of failure of the bus voltage. M-Bus is a bus system used for the remote reading of gas, water, heat, electricity, etc. It also supports various sensors and actuators. This is a cost-optimized bus for the transfer of energy consumption data since it is made for communication on only two wires. M-Bus can be used in the industry, but also, it’s convenient to be used in private households. By the standard, M-Bus master can read up to 250 slave devices. They can be meters, water, electrical, or gas meters. You can also use M-bus in applications like alarm systems, flexible illumination installations, heating control, etc. It
can monitor different consumption meters, and it can monitor any leakage. One of the biggest advantages of M-Bus are that all data reading is accomplished remotely. It is a very simple protocol – it uses only two wires, and it uses power supply from the users which are connected to the wire, and reading errors are minimal. Also, reading is very fast. Further processing is very easy since the received data is presented in a machine readable form. There are no special cables – you can use a telephone cable. With that one cable, you can attach all the meters in the housing with all the meters individually addressable. This way you can have control over each consumption meter while using only one connection cable.
Features overview
Development board
Nucleo-64 with STM32G474R MCU offers a cost-effective and adaptable platform for developers to explore new ideas and prototype their designs. This board harnesses the versatility of the STM32 microcontroller, enabling users to select the optimal balance of performance and power consumption for their projects. It accommodates the STM32 microcontroller in the LQFP64 package and includes essential components such as a user LED, which doubles as an ARDUINO® signal, alongside user and reset push-buttons, and a 32.768kHz crystal oscillator for precise timing operations. Designed with expansion and flexibility in mind, the Nucleo-64 board features an ARDUINO® Uno V3 expansion connector and ST morpho extension pin
headers, granting complete access to the STM32's I/Os for comprehensive project integration. Power supply options are adaptable, supporting ST-LINK USB VBUS or external power sources, ensuring adaptability in various development environments. The board also has an on-board ST-LINK debugger/programmer with USB re-enumeration capability, simplifying the programming and debugging process. Moreover, the board is designed to simplify advanced development with its external SMPS for efficient Vcore logic supply, support for USB Device full speed or USB SNK/UFP full speed, and built-in cryptographic features, enhancing both the power efficiency and security of projects. Additional connectivity is
provided through dedicated connectors for external SMPS experimentation, a USB connector for the ST-LINK, and a MIPI® debug connector, expanding the possibilities for hardware interfacing and experimentation. Developers will find extensive support through comprehensive free software libraries and examples, courtesy of the STM32Cube MCU Package. This, combined with compatibility with a wide array of Integrated Development Environments (IDEs), including IAR Embedded Workbench®, MDK-ARM, and STM32CubeIDE, ensures a smooth and efficient development experience, allowing users to fully leverage the capabilities of the Nucleo-64 board in their projects.
Microcontroller Overview
MCU Card / MCU
Architecture
ARM Cortex-M4
MCU Memory (KB)
512
Silicon Vendor
STMicroelectronics
Pin count
64
RAM (Bytes)
128k
You complete me!
Accessories
Click Shield for Nucleo-64 comes equipped with two proprietary mikroBUS™ sockets, allowing all the Click board™ devices to be interfaced with the STM32 Nucleo-64 board with no effort. This way, Mikroe allows its users to add any functionality from our ever-growing range of Click boards™, such as WiFi, GSM, GPS, Bluetooth, ZigBee, environmental sensors, LEDs, speech recognition, motor control, movement sensors, and many more. More than 1537 Click boards™, which can be stacked and integrated, are at your disposal. The STM32 Nucleo-64 boards are based on the microcontrollers in 64-pin packages, a 32-bit MCU with an ARM Cortex M4 processor operating at 84MHz, 512Kb Flash, and 96KB SRAM, divided into two regions where the top section represents the ST-Link/V2 debugger and programmer while the bottom section of the board is an actual development board. These boards are controlled and powered conveniently through a USB connection to program and efficiently debug the Nucleo-64 board out of the box, with an additional USB cable connected to the USB mini port on the board. Most of the STM32 microcontroller pins are brought to the IO pins on the left and right edge of the board, which are then connected to two existing mikroBUS™ sockets. This Click Shield also has several switches that perform functions such as selecting the logic levels of analog signals on mikroBUS™ sockets and selecting logic voltage levels of the mikroBUS™ sockets themselves. Besides, the user is offered the possibility of using any Click board™ with the help of existing bidirectional level-shifting voltage translators, regardless of whether the Click board™ operates at a 3.3V or 5V logic voltage level. Once you connect the STM32 Nucleo-64 board with our Click Shield for Nucleo-64, you can access hundreds of Click boards™, working with 3.3V or 5V logic voltage levels.
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 Nucleo 64 with STM32G474RE MCU 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 M-Bus Slave Click driver.
Key functions:
mbusslave_generic_write- Generic write function.mbusslave_generic_read- Generic read 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 MBusSlave Click example
*
* # Description
* This example reads and processes data from M-Bus Slave clicks.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes the driver.
*
* ## Application Task
* Depending on the selected mode, it reads all the received data or sends the desired message
* every 2 seconds.
*
* ## Additional Function
* - mbusslave_process ( ) - The general process of collecting the received data.
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "mbusslave.h"
#include "string.h"
#define PROCESS_RX_BUFFER_SIZE 500
#define TEXT_TO_SEND "MikroE - M-Bus Slave click board\r\n"
#define DEMO_APP_RECEIVER
// #define DEMO_APP_TRANSMITTER
// ------------------------------------------------------------------ VARIABLES
static mbusslave_t mbusslave;
static log_t logger;
// ------------------------------------------------------- ADDITIONAL FUNCTIONS
static void mbusslave_process ( void )
{
int32_t rsp_size;
char uart_rx_buffer[ PROCESS_RX_BUFFER_SIZE ] = { 0 };
uint8_t check_buf_cnt;
rsp_size = mbusslave_generic_read( &mbusslave, uart_rx_buffer, PROCESS_RX_BUFFER_SIZE );
if ( rsp_size > 0 )
{
for ( uint8_t cnt = 0; cnt < rsp_size; cnt++ )
{
log_printf( &logger, "%c", uart_rx_buffer[ cnt ] );
if ( uart_rx_buffer[ cnt ] == '\n' )
{
log_printf( &logger, "--------------------------------\r\n" );
}
}
}
}
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
mbusslave_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 ----" );
Delay_ms( 100 );
// Click initialization.
mbusslave_cfg_setup( &cfg );
MBUSSLAVE_MAP_MIKROBUS( cfg, MIKROBUS_1 );
mbusslave_init( &mbusslave, &cfg );
Delay_ms( 100 );
}
void application_task ( void )
{
#ifdef DEMO_APP_RECEIVER
mbusslave_process( );
#endif
#ifdef DEMO_APP_TRANSMITTER
mbusslave_generic_write( &mbusslave, TEXT_TO_SEND, strlen( TEXT_TO_SEND ) );
log_info( &logger, "---- Data sent ----" );
Delay_ms( 2000 );
#endif
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
