The concept of "Arbiter"

Recentely, I read nand flash spec designed by my collegue. From time to time, I'm encountered with the term "arbiter", which makes me confused. What's the true meaning?

 

After looking for some data on the Internet, the explanation to "bus arbiter" is easy to understand. Quoted as follows:

 

"Bus Arbitration

Centralized Bus Arbitration

Centralized bus arbitration requires hardware that will grant the bus to one of the requesting devices. This hardware can be part of the CPU or it can be a separate device on the motherboard. "

From:

"PCI Bus Arbiter

The PCI bus arbiter performs bus arbitration among multiple masters on the PCI bus. Any number of bus masters can reside on the PCI bus, as well as requests for the bus. One pair of request and grant signals is dedicated to each bus master.

The PCI bus arbiter implements either rotating priority or a fixed priority scheme. In the rotating priority scheme, the requestor that is most recently granted the bus receives the lowest priority, while the requestor position next to it receives the highest priority. The remaining requestor receives subsequently lower priority based on its position.

This megafunction is available in Altera hardware description language (AHDL), Verilog, VHDL, and netlist format. Megafunction sizes vary with features and customization. Eureka Technology can customize the design according to specific user requirements. Please contact Eureka Technology or visit the Eureka Technology web site for a complete data sheet."

From:

My comprehension to "Arbiter"

A device or bus is shared by a mount of externel equipments, "Arbiter" is placed between the device/bus and the externel equipments. while One or more than one equipments requests to use the device/bus, Arbitration is done by the "Arbiter" to decide which one can access the device.

So, "Arbiter" is used to grant certain one of externel equipments to access the device.