Take your motor control experience to the next level with DRV8874 and STM32F091RC
Precise control, endless possibilities
Published Feb 26, 2024
Click board™
DC Motor 15 Click
Dev Board
Nucleo-64 with STM32F091RC MCU
Compiler
NECTO Studio
MCU
STM32F091RC
Embrace the power of brushed motor control today and automagically regulate the current during the Start-up sequence of a DC motor!
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Hardware Overview
How does it work?
DC Motor 15 Click is based on the DRV8874, an integrated motor driver with N-channel H-bridge, charge pump, current sensing and proportional output, current regulation, and protection circuitry from Texas Instruments. The DRV8874 operates from the external power supply from 4.5V to 37V, providing a wide range of output load currents for various motors and loads. The charge pump feature improves efficiency by supporting N-channel MOSFET half-bridges and 100% duty cycle driving. This Click board™ also integrates current sensing, regulation, and feedback. These features allow the DRV8874 to sense the output current without an external sense resistor or sense circuitry reducing system cost and complexity. This also allows the device to limit the output current in the case of the motor stall or high torque events and give detailed feedback to the MCU about the load
current through a proportional output on the AN pin of the mikroBUS™, labeled as IPR. The DRV8874 integrates an H-bridge output power stage that can be operated in different control modes by the PMODE pin setting. The PMODE pin on this Click board™ is set to a logic low level, meaning the device is latched into PH/EN mode. PH/EN mode allows the H-bridge to be controlled with a speed and direction type of interface through two GPIO pins labeled IN2 and IN1, routed to the PWM and CS pins of the mikroBUS™ socket. It also has a Sleep Mode that achieves ultra-low quiescent current draw by shutting down most of the internal circuitry. The SLP pin routed to the RST pin of the mikroBUS™ socket provides an ultra-low power mode to minimize current draw during system inactivity. As mentioned in the product description, DC Motor 15 Click communicates with MCU using several GPIO pins.
In addition to the pins used to adjust the speed and rotation direction of the motor, this Click board™ also has an interrupt labeled as FLT routed to the INT pin of the mikroBUS™ socket used to protect the device and the output load. The DRV8874 enters Fault Mode when a fault is encountered, leaves Fault Mode, and re-enters Active Mode when the recovery condition is met. 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. However, the 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
Nucleo-64 with STM32F091RC 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-M0
MCU Memory (KB)
256
Silicon Vendor
STMicroelectronics
Pin count
64
RAM (Bytes)
32768
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.
DC Gear Motor - 430RPM (3-6V) represents an all-in-one combination of a motor and gearbox, where the addition of gear leads to a reduction of motor speed while increasing the torque output. This gear motor has a spur gearbox, making it a highly reliable solution for applications with lower torque and speed requirements. The most critical parameters for gear motors are speed, torque, and efficiency, which are, in this case, 520RPM with no load and 430RPM at maximum efficiency, alongside a current of 60mA and a torque of 50g.cm. Rated for a 3-6V operational voltage range and clockwise/counterclockwise rotation direction, this motor represents an excellent solution for many functions initially performed by brushed DC motors in robotics, medical equipment, electric door locks, and much more.
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 STM32F091RC MCU as your development board.
Track your results in real time
Application Output via Debug Mode
1. Once the code example is loaded, pressing the "DEBUG" button initiates the build process, programs it on the created setup, and enters Debug mode.
2. After the programming is completed, a header with buttons for various actions within the IDE becomes visible. Clicking the green "PLAY" button starts reading the results achieved with the Click board™. The achieved results are displayed in the Application Output tab.
Software Support
Library Description
This library contains API for DC Motor 15 Click driver.
Key functions:
void dcmotor15_forward ( );- Function is used to drive the motor forward.void dcmotor15_reverse ( );- Function is used to drive the motor in reverse.void dcmotor15_brake ( );- Function is used to brake the motor.
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 DC Motor 15 Click Example.
*
* # Description
* This example demonstrates the use of DC Motor 15 click board.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes the driver and makes an initial log.
*
* ## Application Task
* Drives the motor in the forward direction for 5 seconds, then pulls brake for 2 seconds,
* and after that drives it in the reverse direction for 5 seconds, and finally,
* disconnects the motor for 2 seconds. It will also calculates and displays the motor current consumption.
* Each step will be logged on the USB UART where you can track the program flow.
*
* @author Stefan Filipovic
*
*/
#include "board.h"
#include "log.h"
#include "dcmotor15.h"
// Number of ADC conversions that will be performed for a single current measurement.
#define NUM_OF_ADC_CONVERSATIONS 1000
// Time period for forward and reverse modes in seconds.
#define RUN_PERIOD 6
// Time period for brake and stop modes in seconds.
#define IDLE_PERIOD 3
static dcmotor15_t dcmotor15; /**< DC Motor 15 Click driver object. */
static log_t logger; /**< Logger object. */
void display_current ( dcmotor15_t *ctx, uint16_t delay )
{
float current = 0;
for ( uint8_t cnt = 0; cnt < delay; cnt++ )
{
Delay_ms( 1000 );
current = dcmotor15_get_current ( &dcmotor15, NUM_OF_ADC_CONVERSATIONS );
log_printf( &logger, " Current : %.3f [A]\r\n", current );
}
log_printf( &logger, " ------------------------------\r\n" );
}
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
dcmotor15_cfg_t dcmotor15_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 );
Delay_ms( 100 );
log_info( &logger, " Application Init " );
// Click initialization.
dcmotor15_cfg_setup( &dcmotor15_cfg );
DCMOTOR15_MAP_MIKROBUS( dcmotor15_cfg, MIKROBUS_1 );
if ( ADC_ERROR == dcmotor15_init( &dcmotor15, &dcmotor15_cfg ) )
{
log_error( &logger, " Application Init Error. " );
log_info( &logger, " Please, run program again... " );
for ( ; ; );
}
dcmotor15_default_cfg ( &dcmotor15 );
log_info( &logger, " Application Task " );
}
void application_task ( void )
{
log_printf( &logger, " The motor turns forward! \r\n" );
dcmotor15_forward( &dcmotor15 );
display_current ( &dcmotor15, RUN_PERIOD );
log_printf( &logger, " Pull brake! \r\n" );
dcmotor15_brake( &dcmotor15 );
display_current ( &dcmotor15, IDLE_PERIOD );
log_printf( &logger, " The motor turns in reverse! \r\n" );
dcmotor15_reverse( &dcmotor15 );
display_current ( &dcmotor15, RUN_PERIOD );
log_printf( &logger, " The motor is disconnected (High-Z)! \r\n" );
dcmotor15_stop( &dcmotor15 );
display_current ( &dcmotor15, IDLE_PERIOD );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
