HP 81200, User Manual, Page: 41 / 240

Data Generation Principles Introduction to the System
HP 81200 Data Generator/Analyzer Platform User Guide, Revision 2.1
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If you had chosen a memory type segment, this segment would start from
the beginning with every loop. If the segment is larger than the portion
used in the sequence, then there is data that is never generated in this
sequence.
However, this is different when looping blocks with PRBS/PRWS
segments.
Looping Blocks With PRBS/PRWS Segments
If you do not use the complete PRxS you have chosen for your application
but are looping it, then with each new loop cycle the next portion of the
PRxS is used, when the looping is going on.
It can happen that the next portion is the rest of the PRxS and a bit of the
beginning. The portioning of the PRxS will go on as long as the looping
lasts.
The data representation in the HP 81200 system memory and the data
stream output for one connector may look as follows:
Figure 10 PRBS Memory Representation and Generated Data Stream
Hardware Dependencies
The number of blocks and loops that can be used depends on the
sequencer used.
Generating Loops With the HP E4831A Clock Module
For the E4831A Clock Module we have the following capabilities:
•
1 counted loop level with up to 30 counted loops altogether. A counted
loop may count up to 2
20
.
• 1 infinite loop in loop level 2
•
Up to 60 blocks: # #counted loops
=
60.
Example: 60 blocks can be used if no counted loop is used. Up to 30
blocks can each be looped. With 45 blocks up to 15 counted loops can be
used (for example always loop 3 blocks).
Max Memory for each Connector
32 K for 2
15
– 1 PRBS
1 word for Pause0
...
1k 1k
64 bit Pause
...
Data Stream Output
Memory Representation
(64 K * Blocklength Granularity)