The arbiter might eliminate GNT# Anytime. A device that loses GNT# could comprehensive its existing transaction, but may not start off a person (by asserting FRAME#) Unless of course it observes GNT# asserted the cycle in advance of it commences. PCI offers separate memory and memory-mapped I/O port tackle spaces https://nathanlabsadvisory.com/the-top-benefits-of-using-ciso-as-a-service/