The PCI32 User Guide states that S_WRDN is valid during ADDR_VLD and held through the entire transaction. Is this correct?
S_WRDN is sampled on the next clock after the assertion of ADDR_VLD. It indicates a WRITE when asserted High and a READ when asserted Low.
ADDR_VLD is asserted only during the address phase, while S_WRDN remains at a stable value until the end of the transaction.