This code example demonstrates how to receive CAN messages over the CAN bus using XMC™ MCU. This code example can be used together with the CAN transmitter example running on another board.

View this README on GitHub.

Provide feedback on this code example.

• ModusToolbox™ software v3.0
• SEGGER J-Link software
• Programming language: C
• Associated parts: All XMC™ MCU parts

• GNU Arm® embedded compiler v10.3.1 (GCC_ARM) - Default value of TOOLCHAIN

• XMC1400 boot kit (KIT_XMC14_BOOT_001) - Default value of TARGET
• XMC4200 Platform2Go kit (KIT_XMC_PLT2GO_XMC4200)
• XMC4300 relax EtherCAT kit (KIT_XMC43_RELAX_ECAT_V1)
• XMC4400 Platform2Go kit (KIT_XMC_PLT2GO_XMC4400)
• XMC4500 relax kit (KIT_XMC45_RELAX_V1)
• XMC4700 relax kit (KIT_XMC47_RELAX_V1)
• XMC4800 relax EtherCAT kit (KIT_XMC48_RELAX_ECAT_V1)

This example uses the board's default configuration. See the kit user guide to ensure that the board is configured correctly.

Two XMC MCU boards are required to test this code example: one for the XMC™ MCU: CAN receiver application and the other for the XMC™ MCU: CAN transmitter application. See Supported kits.

Connect the CANH and CANL of one board to the CANH and CANL of the other board respectively to establish CAN communication between the transmitter and the receiver node. Also connect the ground pin of both boards together.

Table 1. CAN board connections

Notes:

• The KIT_XMC_PLT2GO_XMC4200 and KIT_XMC43_RELAX_ECAT_V1 kits provide the CAN interface via a D-Sub DE-9 connector. Therefore, you might need a DBP connector or DB9 to RS232/ RS485 convertor board to connect these boards.

• The KIT_XMC45_RELAX_V1 kit does not have an external CAN transceiver. Therefore, you need to connect an external CAN transceiver to the CAN Tx and Rx pins.

• The CAN bus lines (CANH and CANL signals) of the on-board transceiver in the KIT_XMC47_RELAX_V1 and KIT_XMC_PLT2GO_XMC4400 kits are not terminated by a 120 Ω resistor and must be terminated externally. Add a 120 Ω termination resistor between the CANH and CANL pins for proper operation of CAN.

• The CAN bus lines (CANH and CANL signals) of the on-board transceiver in the KIT_XMC47_RELAX_V1 kit are not terminated by a 120 Ω resistor and must be terminated externally. Add a 120 Ω termination resistor between the CANH and CANL pins for proper operation of CAN as shown in Figure 1.

Figure 1. Hardware setup

Install a terminal emulator if you don't have one. Instructions in this document use Tera Term.

This example requires no additional software or tools.

Create the project and open it using one of the following:

project-creator-cli --board-id KIT_XMC14_BOOT_001 --app-id mtb-example-xmc-can-receiver --user-app-name CANReceiver --target-dir "C:/mtb_projects"

library-manager-cli --project "C:/mtb_projects/CANReceiver" --add-bsp-name KIT_XMC47_RELAX_V1 --add-bsp-version "latest-v4.X" --add-bsp-location "local"

library-manager-cli --project "C:/mtb_projects/CANReceiver" --set-active-bsp APP_KIT_XMC47_RELAX_V1

1. Connect the board to your PC using a micro-USB cable through the debug USB connector.

2. Program the board using Eclipse IDE for ModusToolbox™ software:

   1. Select the application project in the Project Explorer.

   2. In the Quick Panel, scroll down, and click <Application Name> Program (JLink).

3. Connect the second board running the CAN transmitter example as described in the Hardware setup section.

4. Confirm that User LED1 of the receiver board toggles, indicating that the CAN messages are received successfully.

5. Press the user button (BUTTON1) on the transmitter board and confirm that the User LED2 on the receiver board is updated accordingly.

6. To view the received CAN message in a serial terminal, open a terminal program and select the JLink CDC COM port. Set the serial port parameters to 8N1 and 115200 baud. Confirm that the received CAN message is displayed in the serial terminal as shown in Figure 2.

Figure 2. Log messages

Note: KIT_XMC45_RELAX_V1 kit does not have an onboard USB-UART bridge to view the terminal logs. Connect an external USB-UART bridge to the UART pins to view the log messages.

You can debug the example to step through the code. In the IDE, use the <Application Name> Debug (JLink) configuration in the Quick Panel. For more details, see the "Program and debug" section in the Eclipse IDE for ModusToolbox™ software user guide.

In this code example, the CAN Node 1 is linked with message object 0 (MO0), which is configured to receive a single byte over the CAN bus. A successful reception of the message is indicated by toggling user LED1. The incoming CAN messages can be seen in the serial terminal using UART communication. The status of the user LED2 is updated based on the incoming CAN message.

Figure 3. Firmware flow

The project uses a custom design.modus file since the following settings were modified in the default design.modus file.

Figure 4. CAN RX pin settings

Figure 5. CAN TX pin settings

Figure 6. USIC (UART) settings

Figure 7. USIC interrupt settings

Figure 8. UART TX pin settings

Figure 9. UART RX pin settings

Infineon provides a wealth of data at www.infineon.com to help you select the right device, and quickly and effectively integrate it into your design.

For XMC™ MCU devices, see 32-bit XMC™ Industrial microcontroller based on Arm® Cortex®-M.

Document title: CE232627 - XMC™ MCU: CAN receiver

All other trademarks or registered trademarks referenced herein are the property of their respective owners.

© 2022 Infineon Technologies AG

All Rights Reserved.

The information given in this document shall in no event be regarded as a guarantee of conditions or characteristics. With respect to any examples or hints given herein, any typical values stated herein and/or any information regarding the application of the device, Infineon Technologies hereby disclaims any and all warranties and liabilities of any kind, including without limitation, warranties of non-infringement of intellectual property rights of any third party.

For further information on technology, delivery terms and conditions and prices, please contact the nearest Infineon Technologies Office (www.infineon.com).

Due to technical requirements, components may contain dangerous substances. For information on the types in question, please contact the nearest Infineon Technologies Office.

Infineon Technologies components may be used in life-support devices or systems only with the express written approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure of that life-support device or system or to affect the safety or effectiveness of that device or system. Life support devices or systems are intended to be implanted in the human body or to support and/or maintain and sustain and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may be endangered.