Chapter 4: Using the Logic Analyzer in Eye Scan Mode

Setting Up and Running Eye Scan Measurements

 

The qualifier is changed on the second clock cycle of the burst. It

 

remains stable until after the next clock cycle following the end of the

 

burst. If the clock pauses between bursts (as shown above), then the

 

qualifier level for the previous burst remains in place until the second

 

clock cycle of the next burst.

 

If the clock free-runs between bursts, then the qualifier should be

 

taken false on the cycle following the end of the burst, and returned

 

true on the second cycle of the next burst (if that burst is to be

 

qualified for eye scan). If each burst is only one clock cycle (two data

 

transfers), then the qualifier will be changing on the first edge of each

 

burst, but the level will be for the previous burst. Variable size bursts

 

are supported.

 

 

NOTE:

If you have more than one logic analyzer card, the following procedure applies

 

to the master card. The master card is the one that receives the clock signal

 

from the target system on its J clock input.

 

 

Procedure

First, set up the sampling position for the qualifier

 

1. Connect the qualification signal from your target system to the Pod A2

 

clock (the K clock) input of the master logic analyzer card.

 

2. On the Sampling tab, select the State Mode button, and select 800 Mb/s

 

acquisition mode.

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Agilent Technologies 16760A manual Clock cycle of the next burst, Are supported, 125