TCAN1145-Q1: Wake up event recorf by CANINT register bits

Hi Frank,

This is weird, so the node has been waked correctly by WUF, but CANINT doesn't set? Does your software automatically clear the interrupt after CANINT set?

Can you capture some waveforms shows the INH, SDI and SDO outputs?

Regards,

Sean

Hi Sean,

Will provide the waveforms tomorrow.

There is only a read operation on CANINT during the initialization, only check the device register ID.

Thanks

Best,

Frank

Hi Frank,

Are they able to read the CANINT bit after wale up? (INH goes to high)

Regards,

Sean

Hi Sean,

There is no difference on these three signals between normal operation and wake up cannot assert. Yellow is INH, purple is SDI, blue is SDO.

Reading CANINT register is during the initialization. Before read CANINT, the only operation on TCAN1145 is read the register ID. There is nothing to do on CANINT.

We can read the CANINT bit after INH pulled high. We suppose the CANINT can be read as long as the SPI is working well.

Thanks

Best,

Frank

Hi Frank,

Frank QIN said:

We can read the CANINT bit after INH pulled high.

So do you mean after transceiver being waked up (INH pulled high), you read CANINT bit, but it was not set to 1 (still 0). Am I understanding correctly?

Was CANINT flag 0 before the transceiver enters sleep mode?

Regards,

Sean

Hi Sean,

We tried to read it periodicity, it is always 0. From power up to power down, it is always 0.

Thanks,

Best,

Frank

Hi Frank,

The CANINT bit will be set if the device has first been put in sleep mode and then seen an wake up event such as a wake up frame (WUF), so always 0 is abnormal.

Would they try not to use selective wakeup, just use normal wake up pattern (WUP) to see if CANINT will be set?

Regards,

Sean