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5 threshold events – Intel NETWORK PROCESSOR IXP2800 User Manual

Page 388

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388

Hardware Reference Manual

Intel

®

IXP2800 Network Processor

Performance Monitor Unit

11.4.5

Threshold Events

These are the outputs of the threshold comparators. When the value in a data register is compared

to its corresponding counter value and the condition is true, a threshold event is generated.

This results in:

A pulse on the signal lines that are routed to the event’s input port (one signal line from each

comparator).

One piece of functionality this enables is to allow for CHAP commands to be completed only
when a Threshold Event occurs. In other words, a Threshold Event can be used as a Command

Trigger to control the execution of any CHAP command (start, stop, sample, etc.). See

Table 154

.

Table 154. Chap Counter Threshold Events (Design Block # 0001)

Multiplexer #

Event Name

Clock

Domain

Single

pulse/

Long

pulse

Burst

Description

000

Counter 0 Threshold

P_CLK

single

separate

Threshold Condition True on
Event Counter 0

001

Counter 1 Threshold

P_CLK

single

separate

Threshold Condition True on
Event Counter 1

010

Counter 2 Threshold

P_CLK

single

separate

Threshold Condition True on
Event Counter 2

011

Counter 3 Threshold

P_CLK

single

separate

Threshold Condition True on
Event Counter 3

100

Counter 4 Threshold

P_CLK

single

separate

Threshold Condition True on
Event Counter 4

101

Counter 5 Threshold

P_CLK

single

separate

Threshold Condition True on
Event Counter 5