Segment Properties - HP 81200 User Manual

Data Generation Principles
HP 81200 Data Generator/Analyzer Platform User Guide, Revision 2.1
Segments are stored in a segment pool, which is part of the system
database. There is one segment pool with global scope and one segment
pool with local scope.
• Segments in the local segment pools can only be accessed if the
appropriate setting is loaded.
• Segments in the global segment pool can be accessed from any setting.
Using the "local" segment pool makes it easy to export all the segments
required by the current setting if the setting is going to be exported to
another system.

Segment Properties

We differentiate between memory segments and PRBS/PRWS segments.
PRBS/PRWS segments are defined by the polynomial to be used.
Memory segments consist of vectors and traces. A vector specifies all the
parallel bits of a port. The serial bitstream of a terminal line is called trace.
Data Memory Usage
To understand data memory consumption in sequence mode it is best to
think in data words. A word consists of 1 to 16 Bits, depending on the
blocklength granularity and the frequency multiplier of the specific
channel.
• One word is reserved for internal use.
• A PRBS/PRWS segment consumes as many words as its polynomial
says. A 2
• Even if you don't use a PRBS, there is a 2
which means 31 words are allocated.
• A pseudo segment (Pause0/1, for example) consumes 1 word, if such a
segment is used at all channels of the module.
• The remaining memory is used for the programmable data segments.
Segment Type Combinations
General A generator/analyzer module can only execute either memory type
segments or PRBS/PRWS segments at the same time.
Exceptions PRBS/PRWS can also be combined with Pause 0/1, Expected 0/1,
Don'tCare. That means that such a channel must always use that segment
when PRBS segments are used on that module.
Pause0/Pause1, Expected0/Expected1, Don'tCare segments save memory
if all channels of the module execute such type of segments at the same
time.
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–1 PRBS, for example, consumes 32767 words.
Introduction to the System
5
–1 PRBS allocated internally,
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