Reduce noise pollution with actionable data and insights using MCP4921 and TM4C129ENCPDT
Respond promptly to noise-related issues
Published Oct 02, 2023
Click board™
Noise Click
Dev. board
Fusion for Tiva v8
Compiler
NECTO Studio
MCU
TM4C129ENCPDT
Our noise detection solution is engineered to identify and mitigate disruptive noise, fostering quieter and more peaceful environments
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Hardware Overview
How does it work?
Noise Click is based on the MCP4921, a 12-bit DAC with an SPI interface from Microchip. This single-channel DAC has a rail-to-rail output, a fast-setting time, and 450KHz of multiplier mode. The MCP4921 on the Noise Click sets the threshold in 12-bit resolution steps from 0 up to 4096. The noise from the environment this Click board™ receives through the MM034202-11, an analog MEMS microphone from DB Unlimited. It has omnidirectional directivity, a sensitivity of around -42dB, a signal-to-noise ratio of 59dB, and works in a frequency range from 100 up to 10000Hz. This Click board™ also includes two MCP6022s, a rail-to-rail input/output 10MHz Op Amps from Microchip. The operational amplifiers feature wide bandwidth up to 10MHz, low noise, low input offset voltage, and low distortion. The first MCP6022
processes the microphone signal. Then, the amplified voltages pass through the LTC1966, a precision micropower ∆∑ RMS-to-DC converter from Analog Devices. This converter has constant bandwidth independent of the input voltage, flexible rail-to-rail inputs, and outputs and is more accurate than conventional log antilog similar RMS-to-DC converters. After processing with the LTC1966, the signal then goes into the second operational amplifier, which functions as a voltage comparator, from which the interrupt signal originates. To avoid triggering the interrupt hundreds of times per second as ambient noise oscillates near the threshold, a hysteresis circuit is also employed. For that purpose, the Noise Click comes with the MAX6106, a low-cost, micropower, low-dropout, high-output-current voltage
reference of 2.048V from Analog Devices. The Noise Click uses an SPI serial interface to communicate with the host MCU over the mikroBUS™ socket. The LTC1966 RMS-to-DC converter can be turned off with the HIGH logic state on the EN pin of the mikroBUS™ socket. No matter the logic state on the enable pin, the voltage levels can still be monitored over the AN pin. When the ambient noise reaches the set threshold, the interrupt INT pin is pulled HIGH. 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
Fusion for TIVA v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports a wide range of microcontrollers, such as different 32-bit ARM® Cortex®-M based MCUs from Texas Instruments, regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer over a WiFi network. The development board is well organized and designed so that the end-user has all the necessary elements, such as switches, buttons, indicators, connectors, and others, in one place. Thanks to innovative manufacturing technology, Fusion for TIVA v8 provides a fluid and immersive working experience, allowing access
anywhere and under any circumstances at any time. Each part of the Fusion for TIVA v8 development board contains the components necessary for the most efficient operation of the same board. An advanced integrated CODEGRIP programmer/debugger module offers many valuable programming/debugging options, including support for JTAG, SWD, and SWO Trace (Single Wire Output)), and seamless integration with the Mikroe software environment. Besides, it also includes a clean and regulated power supply module for the development board. It can use a wide range of external power sources, including a battery, an external 12V power supply, and a power source via the USB Type-C (USB-C) connector.
Communication options such as USB-UART, USB HOST/DEVICE, CAN (on the MCU card, if supported), and Ethernet is also included. In addition, it also has the well-established mikroBUS™ standard, a standardized socket for the MCU card (SiBRAIN standard), and two display options for the TFT board line of products and character-based LCD. Fusion for TIVA v8 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
Type
8th Generation
Architecture
ARM Cortex-M4
MCU Memory (KB)
1024
Silicon Vendor
Texas Instruments
Pin count
128
RAM (Bytes)
262144
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 Fusion for Tiva v8 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 Noise Click driver.
Key functions:
noise_set_cmd_reg- This function sets command registernoise_set_state- This function switches click ON or OFFnoise_read_an_pin_voltage- This function reads results of AD conversion of the AN pin and converts them to proportional voltage level
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 Noise click example
*
* # Description
* This example performs an ambient noise monitoring using the Noise click board.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Device initialization.
*
* ## Application Task
* Reads the voltage from AN pin which presents the noise level and displays it
* on the USB UART every 5ms. If the noise is above predefined threshold
* (25 percents of max noise, i.e. about 0.4V) an alarm message is being shown.
*
* @note
* We recommend using the SerialPlot tool for data visualizing.
*
* \author MikroE Team
*
*/
#include "board.h"
#include "log.h"
#include "noise.h"
static noise_t noise;
static log_t logger;
void application_init ( void )
{
log_cfg_t log_cfg;
noise_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.
noise_cfg_setup( &cfg );
NOISE_MAP_MIKROBUS( cfg, MIKROBUS_1 );
noise_init( &noise, &cfg );
noise_default_cfg( &noise );
}
void application_task ( void )
{
float voltage = 0;
if ( NOISE_OK == noise_read_an_pin_voltage ( &noise, &voltage ) )
{
log_printf( &logger, "%.3f\r\n", voltage );
}
if ( noise_check_int_pin( &noise ) )
{
log_printf( &logger, " Sound overlimit detected!\r\n" );
}
Delay_ms ( 5 );
}
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
/*!
* \file
* \brief Noise click example
*
* # Description
* This example performs an ambient noise monitoring using the Noise click board.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Device initialization.
*
* ## Application Task
* Reads the voltage from AN pin which presents the noise level and displays it
* on the USB UART every 5ms. If the noise is above predefined threshold
* (25 percents of max noise, i.e. about 0.4V) an alarm message is being shown.
*
* @note
* We recommend using the SerialPlot tool for data visualizing.
*
* \author MikroE Team
*
*/
#include "board.h"
#include "log.h"
#include "noise.h"
static noise_t noise;
static log_t logger;
void application_init ( void )
{
log_cfg_t log_cfg;
noise_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.
noise_cfg_setup( &cfg );
NOISE_MAP_MIKROBUS( cfg, MIKROBUS_1 );
noise_init( &noise, &cfg );
noise_default_cfg( &noise );
}
void application_task ( void )
{
float voltage = 0;
if ( NOISE_OK == noise_read_an_pin_voltage ( &noise, &voltage ) )
{
log_printf( &logger, "%.3f\r\n", voltage );
}
if ( noise_check_int_pin( &noise ) )
{
log_printf( &logger, " Sound overlimit detected!\r\n" );
}
Delay_ms ( 5 );
}
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
