User guide

Introduction to Burst Sync Mode
The burst sync mode is a special operating mode for measuring data in bursts of
bits, rather than one continuous stream of bits.
The burst sync mode measures bit error rates for each burst of data after the error
detector synchronizes to the incoming pattern. The signal at the Gate In port
controls the timing of synchronization and error counting for each burst.
This function is useful, for example, to analyze recirculating loop data. With a
recirculating loop you can simulate very long cable connections like transoceanic
cables. Data is sent into a looped cable drum and after a certain number of loops
it is diverted into the error detector. This way, only a short burst of valid data
reaches the Serial BERT followed by a long break. Therefore, the error detector
needs to be synchronized at the beginning of every burst.
N O T E
The burst sync mode is disabled in "8B/10B Comparison", "Bit Comparison without
PCIe3 SKPOS" and "Bit Comparison without USB3.1 SKPOS" error ratio modes.
Setting up the Error Detector 5
Agilent J-BERT N4903B High-Performance Serial BERT 211