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Bus arbitration
Bus arbitration is a mechanism used in computer architecture to determine which bus segment should be assigned to a specific data transfer. This process involve...
Bus arbitration is a mechanism used in computer architecture to determine which bus segment should be assigned to a specific data transfer. This process involve...
Bus arbitration is a mechanism used in computer architecture to determine which bus segment should be assigned to a specific data transfer. This process involves the following steps:
Initiation: When a data transfer starts, the requesting bus master sends out a request signal to all connected bus slaves.
Collision Detection: Each slave monitors the bus activity on its own bus segment. If multiple requests are received on the same bus segment at the same time, a collision is detected.
Bus Master Mediation: If multiple requests are detected, the bus master takes over and mediates the bus allocation. It decides which bus segment should be assigned to the requesting bus master based on a pre-defined arbitration scheme, such as round-robin or a weighted fair queue.
Bus Arbitration Process: The bus master broadcasts the bus allocation decision to all connected slaves. The requesting bus master then sends a data transfer request to the assigned bus segment.
Example:
Imagine a system with two buses, A and B, connected to a CPU. Bus A is assigned to the CPU, while bus B is assigned to a memory device. When the CPU wants to access memory, it sends a data transfer request to bus B. Bus B detects the collision and informs the bus master. The bus master then assigns the bus to the CPU, allowing the data transfer to proceed