Gadgets Are needed to stick to a protocol so the interrupt-ask for (IRQ) lines is often shared. The PCI bus contains 4 interrupt strains, INTA# via INTD#, all of which can be obtained to each system. Up to 8 PCI devices share a similar IRQ line (INTINA# by way of https://nathanlabsadvisory.com/key-components-of-a-successful-incident-response-strategy/