Gadgets Are needed to abide by a protocol so that the interrupt-request (IRQ) lines can be shared. The PCI bus features 4 interrupt strains, INTA# by INTD#, all of which are offered to each gadget. Up to 8 PCI devices share the exact same IRQ line (INTINA# through INTINH#) in https://nathanlabsadvisory.com/iot-testing-in-the-usa-protect-your-devices-from-cyber-threats/