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Chapter 2: Probing and Selecting the Sampling Mode
Choosing the Sampling Mode
To select the timing mode
1. Open the logic analyzer Setup window.
2. Select the Sampling tab.
3. Choose the Timing Mode option.

You can also select the timing sampling mode in the “Pod Assignment

Dialog” on page 175.

To select the conventional/transitional configuration
1. In the Sampling tab with Timing Mode selected, select the timing analyzer
configuration. You can choose between:
• 800 MHz / 64M Sample Conventional
In this configuration, the analyzer samples and stores measurement
data at each sampling interval, as often as every 1.25 ns.
NOTE: With the Sample Period at 1.25 ns, data is acquired at four times the trigger
sequencer rate. This means that data must be present for at least four samples
before the trigger sequencer can reliably de tect it. The trigger sequencer
could miss data present for less than four sample periods.
The trigger sequencer treats the data as a group of four samples for eac h
sequencer clock. This means that the trigger point indication could be off by
three samples.
Although the trigger sequencer cannot detect all data, the ana lyzer will
correctly capture all data present for at least one sample period.
• 400 MHz / 32M Sample Transitional or Store Qualified
In this configuration, the analyzer samples data at regular intervals, as
often as every 2.5 ns, but only stores the data if it's different than the
previously stored data.
You can further qualify storage of transitions by ignoring data changes
on particular labels.
A time tag is stored with each stored data sample so that all sampled
values can be reconstructed and displayed later.