Experience a new era of brushless motor control with L6235 and PIC18LF4680
Achieve optimal performance effortlessly
Published Nov 01, 2023
Click board™
Brushless 12 Click
Dev Board
EasyPIC v7
Compiler
NECTO Studio
MCU
PIC18LF4680
Don't let your motors be limited. Take action and integrate advanced brushless motor control for limitless possibilities
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Hardware Overview
How does it work?
Brushless 12 Click is based on the L6235, a fully integrated motor driver specifically developed to drive a wide range of BLDC motors with Hall effect sensors from STMicroelectronics. The L6235 includes a 3-phase DMOS bridge, an OFF-TIME PWM current controller, the decoding logic for single-ended Hall sensors that generate the required power stage sequence, and other features for safe operation and flexibility. It also has a built-in Over Current Detection (OCD) that allows protection against short circuits between the outputs and between output and ground. Integrated decoding logic of the L6235 provides the correct sequence on the three outputs labeled as U V W for motors with 60° and 120° spaced Hall effect sensor signals. The sensor outputs are connected to the device's H1, H2, and H3 inputs through the HALL header. H1 input of the L6235 is internally connected to a monostable that provides a width pulse on the TACHO output. With a pull-up resistor on this output, the resulting
waveform at the pin will be a square wave whose frequency is proportional to the motor rotation speed, with an on-time set by the potentiometer VR1 labeled as TACHO. An additional potentiometer on this Click board™ VR2, labeled OFF-TIME, can be used for a PWM current regulation capacity. VR1 potentiometer defines the on-time integration and is compared to a voltage proportional to the desired speed by the Op-Amp LM358 from STMicroelectronics. The output of the Op-Amp represents the speed error signal. Providing this signal to the VREF input of the L6235, which sets the current in the motor windings, the speed error will act on the motor modifying its torque to maintain the speed at a constant value. This feature of the L6235 can be selected by the switch labeled as VREF, which allows the selection between Torque or Speed Mode. Brushless 12 Click communicates with MCU using several GPIO pins. The RST pin of the mikroBUS™ socket labeled EN represents the
Enable function and serves as Chip Enable that turns OFF all power MOSFETs of the L6235. CS pin labeled BRK switches ON all high-side power MOSFETs and allows the user to use the brake function. And the last GPIO pin routed to the PWM pin of the mikroBUS™ socket labeled as F/R selects the direction of the motor rotation. It also possesses two connectors, where one of them represents an external power supply labeled as VIN in the range from 8 to 48V maximum, and the next one labeled with U V W is a terminal on which the BLDC motor needs to be connected. This Click board™ can be operated only with a 5V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. 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
EasyPIC v7 is the seventh generation of PIC development boards specially designed to develop embedded applications rapidly. It supports a wide range of 8-bit PIC microcontrollers from Microchip and has a broad set of unique functions, such as a powerful onboard mikroProg programmer and In-Circuit debugger over USB-B. 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, EasyPIC v7 allows you to connect accessory boards, sensors, and custom electronics more efficiently than ever. Each part of
the EasyPIC 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 various external power sources, including an external 12V power supply, 7-23V AC or 9-32V 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. These sockets cover a wide range of 8-bit PIC MCUs, from PIC10F, PIC12F, PIC16F, PIC16Enh, PIC18F, PIC18FJ, and PIC18FK families. EasyPIC 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
PIC
MCU Memory (KB)
64
Silicon Vendor
Microchip
Pin count
40
RAM (Bytes)
3328
You complete me!
Accessories
Brushless DC (BLDC) Motor with a Hall sensor represents a high-performance motor from the 42BLF motor series. This motor, wired in a star configuration, boasts a Hall Effect angle of 120°, ensuring precise and reliable performance. With a compact motor length of 47mm and a lightweight design tipping the scales at just 0.29kg, this BLDC motor is engineered to meet your needs. Operating flawlessly at a voltage rating of 24VDC and a speed range of 4000 ± 10% RPM, this motor offers consistent and dependable power. It excels in a normal operational temperature range from -20 to +50°C, maintaining efficiency with a rated current of 1.9A. Also, this product seamlessly integrates with all Brushless Click boards™ and those that require BLDC motors with Hall sensors.
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the EasyPIC v7 as your development board.
Track your results in real time
Application Output
After pressing the "FLASH" button on the left-side panel, it is necessary to open the UART terminal to display the achieved results. By clicking on the Tools icon in the right-hand panel, multiple different functions are displayed, among which is the UART Terminal. Click on the offered "UART Terminal" icon.
Once the UART terminal is opened, the window takes on a new form. At the top of the tab are two buttons, one for adjusting the parameters of the UART terminal and the other for connecting the UART terminal. The tab's lower part is reserved for displaying the achieved results. Before connecting, the terminal has a Disconnected status, indicating that the terminal is not yet active. Before connecting, it is necessary to check the set parameters of the UART terminal. Click on the "OPTIONS" button.
In the newly opened UART Terminal Options field, we check if the terminal settings are correct, such as the set port and the Baud rate of UART communication. If the data is not displayed properly, it is possible that the Baud rate value is not set correctly and needs to be adjusted to 115200. If all the parameters are set correctly, click on "CONFIGURE".
The next step is to click on the "CONNECT" button, after which the terminal status changes from Disconnected to Connected in green, and the data is displayed in the Received data field.
Software Support
Library Description
This library contains API for Brushless 12 Click driver.
Key functions:
brushless12_set_brake- This function sets the BRK pin to the desired statebrushless12_set_direction- This function sets the F/R pin to the desired statebrushless12_set_enable- This function sets the EN pin to the desired state
Open Source
Code example
This example can be found in NECTO Studio. Feel free to download the code, or you can copy the code below.
/*!
* @file main.c
* @brief Brushless 12 Click Example.
*
* # Description
* This example demonstrates the use of Brushless 12 click board.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes the driver and sets the click default configuration.
*
* ## 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 pulls brake for 2 seconds.
* 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 "brushless12.h"
static brushless12_t brushless12; /**< Brushless 12 Click driver object. */
static log_t logger; /**< Logger object. */
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
brushless12_cfg_t brushless12_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.
brushless12_cfg_setup( &brushless12_cfg );
BRUSHLESS12_MAP_MIKROBUS( brushless12_cfg, MIKROBUS_1 );
if ( brushless12_init( &brushless12, &brushless12_cfg ) == DIGITAL_OUT_UNSUPPORTED_PIN )
{
log_error( &logger, " Application Init Error. " );
log_info( &logger, " Please, run program again... " );
for ( ; ; );
}
brushless12_default_cfg( &brushless12 );
Delay_ms( 100 );
log_info( &logger, " Application Task " );
}
void application_task ( void )
{
log_printf( &logger, "The motor turns forward! \r\n" );
brushless12_set_direction ( &brushless12, BRUSHLESS12_DIR_FORWARD );
brushless12_set_brake ( &brushless12, BRUSHLESS12_START );
Delay_ms( 5000 );
log_printf( &logger, "Pull brake! \r\n" );
brushless12_set_brake ( &brushless12, BRUSHLESS12_BRAKE );
Delay_ms( 2000 );
log_printf( &logger, "The motor turns in reverse! \r\n" );
brushless12_set_direction ( &brushless12, BRUSHLESS12_DIR_REVERSE );
brushless12_set_brake ( &brushless12, BRUSHLESS12_START );
Delay_ms( 5000 );
log_printf( &logger, "Pull brake! \r\n" );
brushless12_set_brake ( &brushless12, BRUSHLESS12_BRAKE );
Delay_ms( 2000 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
