Flexcan interrupt mode

[jay_zhang]

Hi NXP devs,

I am using S32K144 to make a OBD product, I need to use the interrupt mode of flexcan, but I cannot find the sample code to use the SDK api.

Below code is what I did in my project to initialize the flexcan:

After the initialization, when I send a frame, the callback function is called,

And the code is always print the log, I think I need to clear the send interrupt flag int he callback function, but Id don't know how to do it.

Where I can find the way to do the interrupt mode with flexcan.

Please advice.

[alexandrunan]

The FLEXCAN_DRV_Init install the handlers for the FLEXCAN MBs if you will replace the handlers with your ones the driver will not work anymore. you can use the FLEXCAN_DRV_InstallEventCallback API to signal the handler interruption for diffrent events like send and receive.

[sandeepsandeepk]

Sir how to use event callback function acn you send me the sample to use the CAN with interrupt.

[jay_zhang]

Hi Alexandru,

Thanks for your reply, I tried with FLEXCAN_DRV_InstallEventCallback, it works when I send a can frame, but I cannot get event callback when receiving a can frame before I call FLEXCAN_DRV_Receive function.

So in my mindset, I want to get a receive event when I receive a frame then I can use the receive API to read the frame data.

Can you explain this?

[alexandrunan]

Hello,

You need to call the FLEXCAN_DRV_Receive before seeing the event of callback receive when you see the event of rx complete the message should already be moved in your buffer, because the function will arm the interrupts flags and the callback event signaling will clear the interrupt flag. And if you wish to receive again another message you need to call again the FLEXCAN_DRV_Receive that will rearm the interrupt for a new complete event.

callback function()

{ if(event == RX_COMPLETE)

      FLEXCAN_DRV_Receive;

}

The steps are:

1 Init CAN;

2 Config Callback;

3 call FLEXCAN_DRV_Receive