CAN Interrupt Handle Function Problem

[wolfchip]

Hallo, I'm currently using TC234 AURIX TriCore as my main ECU. How can we know at which point the hardware will trigger CAN Tx-Rx Interrupt Handle Functions? Based on the example from AURIX, it seems that ISR Functions are called once the Tx-Rx Interrupt has been generated. However, I don't know whether which bit(s) is/are SET or CLEAR by user or hardware to trigger those functions? Thank you