Devices are needed to abide by a protocol so the interrupt-ask for (IRQ) lines is usually shared. The PCI bus consists of four interrupt strains, INTA# via INTD#, all of which can be found to each product. Around 8 PCI units share exactly the same IRQ line (INTINA# via INTINH#) https://nathanlabsadvisory.com/ai-chatbox/