Products Are required to observe a protocol so that the interrupt-request (IRQ) traces could be shared. The PCI bus includes four interrupt lines, INTA# as a result of INTD#, all of which are offered to each device. Approximately 8 PCI units share the identical IRQ line (INTINA# by way of https://nathanlabsadvisory.com/the-top-benefits-of-using-ciso-as-a-service/