CAN Bus Click

How does it work?

CAN Bus Click as its foundation uses the MAX13054, ±80V fault-protected CAN-transceiver ideal for industrial network applications that require overvoltage protection from Analog Devices. The MAX13054 provides a link between the CAN protocol controller and the physical wires of the bus lines in a control area network (CAN). These devices can be used for DeviceNet applications, requiring data rates up to 1Mbps. Its input common-mode range is greater than ±12V, exceeding the ISO11898 specification of -2V to +7V, and features ±8kV Contact Discharge protection, making these devices ideal for harsh industrial environments.

Its dominant timeout feature prevents the bus from being blocked by MCU. If the TXD input is held low for greater than 1ms, the transmitter becomes disabled, driving the bus line to a recessive state. In Standby mode, when STB pin routed on the AN and INT pin of the mikroBUS™ socket is set to a high logic state, the transmitter is switched off, and the receiver is switched to a low-current/low-speed state. Activation of Standby mode is possible by setting the onboard SMD jumper labeled as STBY SEL to an appropriate position marked as STB or GND.

The MAX13054 communicates with MCU using the UART interface with the default baud rate of 115200 bps for the data transfer. In addition to UART communication pins from the mikroBUS™ socket, the user can connect the TX/RX signals directly through the UART External header on the right edge of the board. This Click board™ comes equipped with the standard DB-9 connector, making interfacing with the CAN bus simple and easy. Besides, the user can connect the CAN signals directly through the CAN External header, also on the left edge of the board.

The external power supply in a range from 2.7V to 16.5V, next to the D-9 connector, can also be brought to the header labeled BATT on the board’s left side. Through SMD jumpers labeled as 3V3 JMP and 5V JMP, the MAX1658/59 from Analog Devices LDOs output voltages can power up the mikroBUS™ 3.3V and 5V power rails. This feature makes the MAX13054 ideal for many different applications, including those in the automotive market. However, it should be noted that Mikroe does not advise powering up their systems this way. That is why these jumpers are left unpopulated by default.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VIO SEL jumper. It allows for both 3.3V and 5V capable MCUs to use the UART 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.

Specifications

Pinout diagram

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

Notes	Pin					Pin	Notes
Standby Mode	STB	1	AN	PWM	16	NC
	NC	2	RST	INT	15	NC
	NC	3	CS	RX	14	TX	UART TX
	NC	4	SCK	TX	13	RX	UART RX
	NC	5	MISO	SCL	12	NC
	NC	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

CAN Bus Click electrical specifications

Software Support

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

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on mikroE github account.

Library Description

This library contains API for CanBus Click driver.

Key functions:

• canbus_cfg_setup – Config Object Initialization function.
• canbus_init – Initialization function.
• canbus_default_cfg – Click Default Configuration function.

Examples description

This library contains API for CAN Bus click board™. This example transmits/receives and processes data from CAN Bus click. The library initializes and defines the UART bus drivers to transmit or receive data.

The demo application is composed of two sections :

void application_task ( void ) {
   #ifdef TRANSMIT
    
        canbus_send_data( &canbus, demo_message );
        log_printf( &logger, "t%s", demo_message );
        Delay_ms( 2000 );
        log_printf( &logger, "------------------rn" );    
    
    #endif
    
    #ifdef RECIEVER
    
        canbus_process( );

        if ( app_buf_len > 0 ) {
            log_printf( &logger, "%s", app_buf );
            canbus_clear_app_buf(  );
        }
    
    #endif
}

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on mikroE github account.

Other mikroE Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.CanBus

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.