Measure how fast something is rotating in three dimensions with L3GD20 and TM4C129EKCPDT
Spin your projects to success with gyroscopic precision!
Published Jun 20, 2023
Click board™
Gyro Click
Dev Board
Fusion for Tiva v8
Compiler
NECTO Studio
MCU
TM4C129EKCPDT
Low-power three-axis angular rate sensor (gyroscope) designed for precise motion sensing applications
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Hardware Overview
How does it work?
Gyro Click is based on the L3GD20, a high-performance 3-axis gyroscope from STMicroelectronics. The L3GD20 is manufactured using a dedicated micro-machining process developed by STMicroelectronics to produce inertial sensors and actuators on silicon wafers. It is highly configurable with a full-scale programmable range of ±250dps, ±500dps, and ±2000dps, i.e., low range for the high-precision measurement of slow motion and high range used for the measurement of ultra-rapid gestures and movements. This Click board™ allows using both I2C and SPI interfaces with a maximum frequency of 400kHz for I2C and 10MHz for SPI communication. The selection can be made by
positioning SMD jumpers labeled as COMM SEL in an appropriate position. Note that all the jumpers' positions must be on the same side, or the Click board™ may become unresponsive. While the I2C interface is selected, the L3GD20 allows choosing the least significant bit (LSB) of its I2C slave address using the SMD jumper labeled I2C ADD to an appropriate position marked as 0 and 1. The L3GD20 embeds 32 slots of 16-bit data FIFO for each output channel: yaw, pitch, and roll. This feature allows consistent power saving for the system since the host processor does not need to poll data from the sensor continuously but can wake up only when needed and burst the significant data from the FIFO. This buffer can
work in five modes: Bypass mode, FIFO mode, Stream mode, Bypass-to-Stream mode, and Stream-to-FIFO mode. Each mode is selected with the corresponding events detected on the interrupt and data-ready pins, routed to the INT and RST pins on the mikroBUS™ socket. This Click board™ can only be operated with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. However, the Click board™ 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)
512
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 Gyro Click driver.
Key functions:
gyro_get_axis- This function get data from two L3GD20 registergyro_read_gyro- This function read Gyro X-axis, Y-axis and Z-axis axisgyro_read_temperature- This function read temperature data
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 Gyro Click example
*
* # Description
* This example displays values of Gyro sensor (x, y, z axis).
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initialization driver, initialize L3GD20 register and start write log.
*
* ## Application Task
* (code snippet) This is a example which demonstrates the use of Gyro Click board.
* Measured Gyro coordinates ( X-axis, Y-axis, Z-axis ) and temperature in degrees C are being sent
* to the Usart Terminal where you can track their changes.
* All data logs on usb uart for every 2 sec.
*
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "gyro.h"
// ------------------------------------------------------------------ VARIABLES
static gyro_t gyro;
static log_t logger;
static int16_t gyrox;
static int16_t gyroy;
static int16_t gyroz;
static int8_t temperature;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
gyro_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.
gyro_cfg_setup( &cfg );
GYRO_MAP_MIKROBUS( cfg, MIKROBUS_1 );
gyro_init( &gyro, &cfg );
gyro_default_cfg ( &gyro);
}
void application_task ( void )
{
// Task implementation.
gyro_read_gyro( &gyro, &gyrox, &gyroy, &gyroz );
log_printf( &logger, " Axis X : %d \r\n", gyrox );
log_printf( &logger, " Axis Y : %d \r\n", gyroy );
log_printf( &logger, " Axis Z : %d \r\n", gyroz );
log_printf( &logger, "*****************************\r\n" );
Delay_ms( 2000 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
