Gadgets are necessary to abide by a protocol so which the interrupt-ask for (IRQ) traces might be shared. The PCI bus involves four interrupt traces, INTA# through INTD#, all of which are available to each machine. Around 8 PCI equipment share the same IRQ line (INTINA# via INTINH#) in APIC-enabled https://nathanlabsadvisory.com/smart-contract-audit-copyright-companies/