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flexcan_remote_request_non_blocking

flexcan_remote_request_non_blocking#

Overview#

The flexcan_remote_request_non_blocking example shows how to use remote request feature in non-blocking mode by SDK driver.

In this example, 2 boards are connected through CAN bus.

Board A send a remote frame to request message from board B.
After successful request, board A will receive response message.
Board A uses interrupt-driven non-blocking transfer.

Board B receive remote frame and send response message manually with application control.
After successful response, board B will update response message and wait for next remote request.
Board B uses interrupt-driven non-blocking transfer.

Both boards use differnet message buffer to send and receive messages.
Remote request frames are stored in RX message buffer instead of automatic response.

Supported Boards#

MIMXRT1060-EVKB
Hardware requirements

  • Mini/micro USB cable

  • MIMXRT1060-EVKB board

  • Personal Computer

Board settings

The example requires 2 sets of boards, each of them are mounted with the base board. Using a male to male CAN cable to connect the CAN2 instance (J42) between the 2 base boards.

Prepare the Demo

  1. Connect a USB cable between the PC host and the OpenSDA USB on the board.

  2. Open a serial terminal on PC for OpenSDA serial device with these settings:

    • 115200 baud rate

    • 8 data bits

    • No parity

    • One stop bit

    • No flow control

  3. Download the program to the target board.

  4. Either press the reset button on your board or launch the debugger in your IDE to begin running the example.

Running the demo

After connecting the two boards, these instructions display on each terminal window. One board must be chosen as node A and the other board as node B. (Note: Node B should start first) Data is sent continuously between the node A and the node B.

Consider special errata 005829 feature, the 1st valid MB should be used as reserved one.
The TX MB number will change from 8 to 9, while RX MB number will change from 9 to 10 
This message displays on the node A terminal:


******* FLEXCAN RTR Non-Blocking EXAMPLE *******
      Message format: Standard (11 bit id)
      Message buffer 9 used for Rx.
      Message buffer 10 used for Tx.
      Interrupt Mode: Enabled
************************************************

Please select local node as A or B:
Note: Node B should start first.
Node:A
Press any key to trigger one-shot remote request

Remote request message sent
Response message word0: 0x0, word1: 0x55
Response message Timestamp: 63932

Remote request message sent
Response message word0: 0x1, word1: 0x55
Response message Timestamp: 23889

Remote request message sent
Response message word0: 0x2, word1: 0x55
Response message Timestamp: 16638

This message displays on the node B terminal:

******* FLEXCAN RTR Non-Blocking EXAMPLE *******
      Message format: Standard (11 bit id)
      Message buffer 9 used for Rx.
      Message buffer 10 used for Tx.
      Interrupt Mode: Enabled
************************************************

Please select local node as A or B:
Note: Node B should start first.
Node:B
Start to wait request from Node A

Received remote request from Node A
Response message sent
Update next response message.

Received remote request from Node A
Response message sent
Update next response message.

Received remote request from Node A
Response message sent
Update next response message.

Note: This case will be blocked when transferring data on armgcc debug/sdram_debug target. This issue has been fixed in later release by open ERR005829 feature.

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