Introduction to the Flow Control Mechanism

The specification defines the requirements of the Flow Control mechanism by describing conceptual registers and counters along with procedures and mechanisms for reporting, tracking, and calculating whether a transaction can be sent. These elements define the functional requirements; however, the actual implementation may vary from the conceptual model. This section introduces the specified model that serves to explain the concept and define the requirements. The approach taken focuses on a single flow control example for a non-posted header. The concepts discussed apply to all Flow Control buffer types.

The Flow Control Elements

Figure 7-3 identifies and illustrates the elements used by the transmitter ...

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