Ensure the finest levels of motion control with A3908 and ATmega1284
Supercharge your systems with advanced brushed DC motor control
Published Nov 11, 2023
Click board™
DC Motor 25 Click
Dev. board
EasyAVR v7
Compiler
NECTO Studio
MCU
ATmega1284
Experience the future of motion control with our advanced brushed DC motor solution, designed to meet the most demanding industrial applications, from robotics to automation.
A
A
Hardware Overview
How does it work?
DC Motor 25 Click is based on the A3908, a fully integrated low-voltage motor driver for DC motors from Allegro Microsystems. This Click board™ provides all the input and output capabilities necessary to drive DC motors (OUT terminal), alongside monitor diagnostic functions. The A3908 is rated for an operating voltage range compatible with both mikroBUS™ power rails and output currents up to 500mA, programmable via an external I2C-configurable digital potentiometer, the AD5171 from Analog Devices. The A3908 also
has complete protection capabilities like thermal shutdown, undervoltage lockout, and crossover current (shoot-through) protection, allowing robust and reliable operation. Logic pins labeled IN1 and IN2, routed on the default positions of RST and PWM pins of the mikroBUS socket, are provided to control the motor direction of rotation, brake, and standby modes. When both pins are in a high logic state, the A3908 goes into high-side brake mode, which turns on both source drivers. There is no protection during braking, so
care must be taken to ensure that the peak current does not exceed the absolute maximum current. 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. Also, this 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
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)
128
Silicon Vendor
Microchip
Pin count
40
RAM (Bytes)
16384
You complete me!
Accessories
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 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 DC Motor 25 Click driver.
Key functions:
dcmotor25_forward- DC Motor 25 set forward mode function.dcmotor25_reverse- DC Motor 25 set reverse mode function.dcmotor25_brake- DC Motor 25 set brake mode 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 main.c
* @brief DC Motor 25 Click example
*
* # Description
* This example demonstrates the use of DC Motor 25 click board™
* by driving the DC motor in both directions every 3 seconds.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes the I2C driver and performs the click default configuration.
*
* ## Application Task
* This example demonstrates the use of the DC Motor 25 Click board™.
* Drives the motors in the forward and reverse direction
* with a 3 seconds delay with engine braking between direction changes.
* Results are being sent to the UART Terminal, where you can track their changes.
*
* @author Nenad Filipovic
*
*/
#include "board.h"
#include "log.h"
#include "dcmotor25.h"
static dcmotor25_t dcmotor25;
static log_t logger;
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
dcmotor25_cfg_t dcmotor25_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.
dcmotor25_cfg_setup( &dcmotor25_cfg );
DCMOTOR25_MAP_MIKROBUS( dcmotor25_cfg, MIKROBUS_1 );
if ( I2C_MASTER_ERROR == dcmotor25_init( &dcmotor25, &dcmotor25_cfg ) )
{
log_error( &logger, " Communication init." );
for ( ; ; );
}
if ( DCMOTOR25_ERROR == dcmotor25_default_cfg ( &dcmotor25 ) )
{
log_error( &logger, " Default configuration." );
for ( ; ; );
}
log_info( &logger, " Application Task " );
Delay_ms ( 100 );
}
void application_task ( void )
{
log_printf ( &logger, " Forward\r\n" );
dcmotor25_forward( &dcmotor25 );
Delay_ms ( 3000 );
log_printf ( &logger, " Brake\r\n" );
dcmotor25_brake( &dcmotor25 );
Delay_ms ( 3000 );
log_printf ( &logger, " Reverse\r\n" );
dcmotor25_reverse( &dcmotor25 );
Delay_ms ( 3000 );
log_printf ( &logger, " Brake\r\n" );
dcmotor25_brake( &dcmotor25 );
Delay_ms ( 3000 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
