Access control to a shared resource in an asynchronous system

摘要

Independent asynchronous bus master devices share a common bus with control lines serially connecting each bus master in a daisy-chain contiguration. A Bus Acknowledge signal is received by a local bus master which is thereby enabled to seize control of the bus without an input synchronization delay by first inhibiting synchronization means to prevent the passage of the Bus Acknowledge signal to a downstream device for a period of time sufficient to stabilize an output signal indicating such passage. In that manner, the output signal may be used to control the immediate enabling of local bus seizure thereby avoiding local synchronization delay.