TCAN4551-Q1: Interrupt pin

Hi Kei,

Yes, the nINT pin will indicate the status of any unmasked interrupt in the device's interrupt registers. The GPO pins can be mapped to specific interrupts so that the MCU will be able to recognize high priority events without needing a SPI read to determine which interrupt is set. For example when the device receives a new interrupt on the MCAN_INT 0 field to indicate a message has been received (this would be very common during active communication), the nINT pin will assert low to indicate the new interrupt. Typically, the MCU would then need to read the interrupt status register to determine the source of the interrupt before in could read to new data from the RX FIFO or buffer. If the GPO2 pin is configured to indicate this interrupt however, the MCU could recognize the interrupt source from the pin state without needing to read the interrupt status registers and may instead immediately start to read data from the new message. If the nINT pin asserts while the GPO2 signal stays high, the MCU will know some other interrupt has occurred and that it needs to read the interrupt status register in order to determine the source. 

The available configurations for the GPO pins can be seen in the Modes of Operation and Pin Configuration Registers (address = h0800).

Let me know if you have any more questions. 

Regards, 
Eric Schott