A common access ring (CAR) architecture that supports multiple masters and slaves is provided. One or more masters may make a request on the ring at the same time, such that multiple transactions are simultaneously pending. Moreover, multiple masters may simultaneously make a request to the same slave. However, each master cannot make more than one request at a time, and must wait until a current request is completed before making another request. The ring architecture ensures that no more than one request arrives at a slave at any given time. If a request arrives while a slave is processing a previous request, the arriving request is not serviced, and the master that originated the arriving request is asked to retry the request at a later time. Atomic shadow-write operations are supported by including all shadow registers in a dedicated sub-ring of the CAR architecture.