Devices Are required to follow a protocol so the interrupt-ask for (IRQ) traces may be shared. The PCI bus features 4 interrupt strains, INTA# by means of INTD#, all of which are offered to every unit. Around eight PCI products share exactly the same IRQ line (INTINA# via INTINH#) in https://nathanlabsadvisory.com/testing-for-compliance/