Acquisition Data Description - HP 16554A Programmer's Manual

Acquisition Data Description

The acquisition data section consists of a variable number of bytes depending
on the number of cards in the configuration, the acquisition mode, and the
state tag setting. The data is grouped in rows of bytes with one sample from
each pod in a single row. The width of the row is based on the number of
cards in the system. Each card has four pods with two bytes of data per pod.
The clock pod data (four bytes) is always first in the data row. The first two
bytes of the clock pod data are unused. The total number of bytes in a data
row for the various card count configurations is:
Cards Clock Pod Bytes
1 4 bytes
2 4 bytes
3 4 bytes
The sequence of pod data within a row is the same as shown above for the
number of valid rows per pod. The number of valid rows per pod can be
determined by examining bytes 253 through 256 for pod pair 3/4 of the
master card and bytes 257 through 260 for pod pair 1/2 of the master card.
The number of valid rows for other pod pairs is contained in bytes 213
through 252.
A one-card configuration has the following data arrangement (per row):
<clk pod 1> <pod 4> <pod 3> <pod 2> <pod 1>
A two-card configuration has the following data arrangement (per row):
<-----expansion card ------><-------master card-------->
<clk 1><pod 4><pod 3><pod 2><pod 1><pod 4><pod 3><pod 2><pod 1>
A three-card configuration has the following data arrangement per row:
<- high expander -><-lower expander -><---master card--->
<clk 1><pod 4>. . .<pod 1><pod 4>. . .<pod 1><pod 4>. . .<pod 1>
If the data block is unloaded without first using the DBLock command to specify
UNPacked data, this data block description does not apply.
Unused pods always have data, however it is invalid and should be ignored.
DATA and SETup Commands
Acquisition Data Description
Data Bytes Total Bytes Per Row
8 bytes 12 bytes
16 bytes 20 bytes
24 bytes 28 bytes
17–11