How does it work?

CAN 2 FD Click features TLE9255W a CAN protocol controller a part of the Infineon standard HS CAN transceiver family and provides beside CAN partial networking functions also a CAN FD capability up to 5 MBit/s in HS CAN networks. Configured as a partial networking HS CAN transceiver the TLE9255W can drive and receive CAN FD messages. It can also be used to block the payload of CAN FD messages. This CAN FD tolerant feature allows the usage of microcontrollers in CAN FD networks, which are not CAN FD capable. The two non-low power modes (Normal-operating Mode and Receive-only Mode) and the two low power modes (Sleep Mode and Stand-by Mode) provide minimum current consumption based on the required functionality.

The SPI of TLE9255W controls the setup of the wake-up messages and the status message generated by the internal state machine. Most of the functions, including wake-up functions, INH output control, mode control, undervoltage control are configurable by the SPI. This allows a very flexible usage of the TLE9255W in different applications.

High speed CAN (HS CAN) is a serial bus system that connects microcontrollers, sensors and actuators for realtime control applications. ISO 11898-2 (2016) describes the use of the Controller Area Network (CAN) within road vehicles. According to the 7-layer OSI reference model the physical layer of a HS CAN bus system specifies the data transmission from one CAN node to all other available CAN nodes within the network. The CAN transceiver is part of the physical layer.

The HS CAN transceiver TLE9255W includes a receiver and a transmitter unit, allowing the transceiver to send data to the bus medium and monitoring the data from the bus medium at the same time. It converts the serial data stream, which is available on the transmit data input TxD, to a differential output signal on the CAN bus, provided by the CANH and CANL pins. The receiver stage of the TLE9255W monitors the data on the CAN bus and converts it to a serial, single-ended signal on the RxD output pin.

Given all the features its components offer, the CAN FD 2 Click is best used for HS CAN networks in automotive applications and HS CAN networks in industrial applications. The onboard SMD jumper labeled as the VIO SEL is used to select which voltage rail will be used as the logic voltage level. It offers voltage selection between 3.3V and 5V so that the click board™ can be interfaced with both the 3.3V and 5V capable MCUs. The two UART wires (RX and TX) can also be connected directly through two pins to UART External Pads on the left edge of the board. With R6 and R7 jumpers populated alows you to use click board with standard 12V battery connected on Battery Pads at right side of board.

Specifications

Pinout diagram

This table shows how the pinout on CAN FD 2 Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
	NC	1	AN	PWM	16	NC
	NC	2	RST	INT	15	NC
SPI Chip Select	CS	3	CS	RX	14	TX	UART Transmit
SPI Clock	SCK	4	SCK	TX	13	RX	UART Receive
SPI Data OUT	SDO	5	MISO	SCL	12	NC
SPI Data IN	SDI	6	MOSI	SDA	11	NC
Power Supply	3.3V	7	3.3V	5V	10	5V	Power Supply
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

Software Support

We provide a library for the CAN FD 2 Click on our LibStock page, as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Library Description

The library covers all the necessary functions to control CAN FD 2 Click board. Library performs a standard UART communication.

Key functions:

• void canfd2_set_mode ( uint8_t op_mode ) - Set operating mode function.
• void canfd2_read_block ( uint8_t *read_data, uint16_t length ) - Read block function.
• void canfd2_write_block ( uint8_t *write_data, uint16_t length ) - Write block function.

Examples description

The application is composed of three sections :

• System Initialization - Initializes UART, sets CS pins as output.
• Application Initialization - Initialization driver enables - UART and SPI, performs an app mode, also write log.
• Application Task - (code snippet) This is an example that demonstrates the use of the CAN FD 2 Click board. This application task writes message data via UART every 3 seconds. In the second case, checks if new data byte have received in RX buffer ( ready for reading ), and if ready than reads one byte from RX buffer. Results are being sent to the Usart Terminal where you can track their changes.

void application_task ( )
{
    if ( app_mode == APP_MODE_RECEIVER )
    {
        // RECEIVER - UART polling
        char rd_msg[ 10 ] = { 0 };

        canfd2_read_block( &rd_msg[ 0 ], 8 );
        mikrobus_logWrite( rd_msg, _LOG_TEXT );
    }
    else
    {
        // TRANSMITER - TX each 3 sec

        canfd2_write_block( &demo_message_data[ 0 ], 8 );

        Delay_ms( 3000 );
    }
}

The full application code, and ready to use projects can be found on our LibStock page.

Other mikroE Libraries used in the example:

• UART

Additional notes and informations

Depending on the development board you are using, you may need USB UART click, USB UART 2 click or RS232 click to connect to your PC, for development systems with no UART to USB interface available on the board. The terminal available in all MikroElektronika compilers, or any other terminal application of your choice, can be used to read the message.

mikroSDK

This Click board™ is supported with mikroSDK - MikroElektronika Software Development Kit. To ensure proper operation of mikroSDK compliant Click board™ demo applications, mikroSDK should be downloaded from the LibStock and installed for the compiler you are using.

For more information about mikroSDK, visit the official page.

Resources

Downloads