Redefine automotive communication with HS CAN via MCP251863 and STM32F091RC
Where data races at lightning speed
Published Feb 26, 2024
Click board™
MCP251863 Click
Dev. board
Nucleo-64 with STM32F091RC MCU
Compiler
NECTO Studio
MCU
STM32F091RC
Unifying speed and reliability, our high-speed CAN FD transceiver establishes unprecedented standards in automotive diagnostic applications
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Hardware Overview
How does it work?
MCP251863 Click is based on the MCP251863, an IC representing a compact solution containing a CAN FD controller with an SPI interface and a high-speed CAN transceiver from Microchip. The high-speed CAN transceiver provides a physical connection with the CAN bus, while the CAN controller represents an interface between the MCU and the transceiver. The role of the CAN controller is to provide arbitration, message framing, message validation, error detection, message filtering, and more. Among all other tasks, it offers formatted CAN data for the application layer running on the host MCU. The MCP251863 communicates with MCU using the SPI interface, allowing communication speeds up to 5Mbps and supporting Normal and Standby operational modes. Normal mode is engaged when the STB pin, routed on the AN pin of the mikroBUS™ socket, is at the logic low level while its transmit pin is held to a high logic level. While in the Normal mode, the data can be sent and received via the CAN H/L bus lines. The mode
selection can be performed by positioning the SMD jumper labeled as STBY to an appropriate position marked as STBY or ON. In Standby mode, if the STBY jumper is set to the STBY position, the user has the option of activating the Standby mode in two ways, where the selection is made by positioning the SMD jumper labeled as STBY SEL to an appropriate position marked as STBY or INT0. This way, the Standby mode can be activated via the STB pin from the mikroBUS™ socket or by the MCP251863 interrupt signal IN0 routed to the TX pin of the mikroBUS™ socket (the IN0 pin can also be used to alert the MCU about the TX events). In addition, this Click board™ also uses several pins of the mikroBUS™ socket. The CLK pin from the MCP251863 routed to the PWM pin of the mikroBUS™ socket can provide the clock output for the host MCU or represent the start of the frame signal. It is derived from the input clock generated by the onboard chip oscillators, where the onboard SMD jumpers allow frequency selection between 20MHz and 40MHz.
Besides, it also uses two interrupt pins, INT and INT1, routed to the INT and RX pins of the mikroBUS™ socket, respectively. While the INT pin is always an interrupt pin used to alert the MCU of the enabled interrupt event, the INT1 pin alerts the MCU about the RX events (if these interrupts are enabled). In addition, the user can connect the external TX/RX signals to the CAN FD transceiver and CAN bus signals directly through the onboard headers on the left and right sides of the board. This Click board™ comes equipped with the standard DB-9 connector, making interfacing with the CAN bus simple and easy. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VIO 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
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.
DB9 Cable Female-to-Female (2m) cable is essential for establishing dependable serial data connections between devices. With its DB9 female connectors on both ends, this cable enables a seamless link between various equipment, such as computers, routers, switches, and other serial devices. Measuring 2 meters in length, it offers flexibility in arranging your setup without compromising data transmission quality. Crafted with precision, this cable ensures consistent and reliable data exchange, making it suitable for industrial applications, office environments, and home setups. Whether configuring networking equipment, accessing console ports, or utilizing serial peripherals, this cable's durable construction and robust connectors guarantee a stable connection. Simplify your data communication needs with the 2m DB9 female-to-female cable, an efficient solution designed to meet your serial connectivity requirements easily and efficiently.
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
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 MCP251863 Click driver.
Key functions:
mcp251863_transmit_message- Transmits the desired message and checks is message successfully sentmcp251863_receive_message- Receives the message and checks is message successfully receivedmcp251863_operation_mode_select- Function for select operation mode
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 MCP251863 Click example
*
* # Description
* This example demonstrates the use of an MCP251863 Click board by showing
* the communication between the two Click boards configured as a receiver and transmitter.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes the driver and logger, performs the Click default configuration and
* displays the selected application mode.
*
* ## Application Task
* Depending on the selected mode, it sends a desired message using CAN protocol or
* reads all the received data and displays them on the USB UART.
*
* @author Stefan Filipovic
*
*/
#include "board.h"
#include "log.h"
#include "mcp251863.h"
// #define DEMO_APP_TRANSMITTER // Uncomment this line to switch to the transmitter mode
#define DEMO_TEXT_MESSAGE "MikroE"
static mcp251863_t mcp251863;
static log_t logger;
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
mcp251863_cfg_t mcp251863_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.
mcp251863_cfg_setup( &mcp251863_cfg );
MCP251863_MAP_MIKROBUS( mcp251863_cfg, MIKROBUS_1 );
if ( SPI_MASTER_ERROR == mcp251863_init( &mcp251863, &mcp251863_cfg ) )
{
log_error( &logger, " Communication init." );
for ( ; ; );
}
if ( MCP251863_ERROR == mcp251863_default_cfg ( &mcp251863 ) )
{
log_error( &logger, " Default configuration." );
for ( ; ; );
}
#ifdef DEMO_APP_TRANSMITTER
log_printf( &logger, " Application Mode: Transmitter\r\n" );
#else
log_printf( &logger, " Application Mode: Receiver\r\n" );
#endif
log_info( &logger, " Application Task " );
}
void application_task ( void )
{
#ifdef DEMO_APP_TRANSMITTER
if ( MCP251863_OK == mcp251863_transmit_message( &mcp251863, DEMO_TEXT_MESSAGE, strlen( DEMO_TEXT_MESSAGE ) ) )
{
log_printf( &logger, " The message \"%s\" has been sent!\r\n", ( char * ) DEMO_TEXT_MESSAGE );
}
Delay_ms ( 1000 );
Delay_ms ( 1000 );
#else
uint8_t data_buf[ 256 ] = { 0 };
uint16_t data_len = 0;
if ( MCP251863_OK == mcp251863_receive_message( &mcp251863, data_buf, &data_len ) )
{
log_printf( &logger, " A new message has received: \"" );
for ( uint16_t cnt = 0; cnt < data_len; cnt++ )
{
log_printf( &logger, "%c", data_buf[ cnt ] );
}
log_printf( &logger, "\"\r\n" );
}
#endif
}
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
