Units are needed to abide by a protocol so that the interrupt-request (IRQ) lines is often shared. The PCI bus consists of 4 interrupt lines, INTA# by INTD#, all of which are offered to every system. Nearly eight PCI gadgets share the identical IRQ line (INTINA# via INTINH#) in APIC-enabled https://nathanlabsadvisory.com/smart-contract-audit-copyright-companies/