Devices are necessary to adhere to a protocol so the interrupt-ask for (IRQ) lines is often shared. The PCI bus features four interrupt traces, INTA# by INTD#, all of which can be found to each device. Approximately 8 PCI gadgets share the exact same IRQ line (INTINA# via INTINH#) in https://nathanlabsadvisory.com/forensic-audit-cyber-forensics/