7.3.8 Interrupt Pin — Functional Description and Usage (INTB_IN)
The INTB_IN pin is an active low interrupt input pin. The INTB_IN pin may act as an output driver and pull low when PDB is low. This interrupt signal, when configured, propagates to the paired serializer. Consult the appropriate serializer data sheet for details of how to configure this interrupt functionality.
- On the serializer, set register 0xC6 = 1 and 0xC6 = 1
- Deserializer INTB_IN (pin 4) is set LOW by some downstream device.
- Serializer pulls INTB pin LOW. The signal is active LOW, so a LOW indicates an interrupt condition.
- External controller detects INTB = LOW; to determine interrupt source, read ISR register.
- A read to ISR clears the interrupt at the Serializer, releasing INTB.
- The external controller typically must then access the remote device to determine downstream interrupt source and clear the interrupt driving the deserializer INTB_IN. This would be when the downstream device releases the INTB_IN (pin 4) on the deserializer. The system is now ready to return to step (2) at next falling edge of INTB_IN.