Somat eDAQlite - 8 DataModes

I2773-4.4 en
161
Somat eDAQ lite
8 DataModes™
This chapter details the available DataModes and their associated parameters and
discusses data storage and memory considerations. DataModes determine how the
eDAQ
lite stores and displays test data. A DataMode definition consists of a list of
input channels, a data storage/processing rate, triggering conditions and other
parameters specific to the DataMode.
8.1 DataMode™ Memory Consumption
The defined DataModes determine the rate at which the eDAQ lite consumes
memory. There is some overhead for storing the test setup file and other eDAQ
lite
files, but typically these files require much less that 1 MB for most large channel count
test setups and proportionately less for tests with fewer channels.
For SIE data files, there is additional overhead for the data file internal linkage and
consistency check parameters. The overhead is usually insignificant, consuming only
a few percent of the data file.
For SIF data files, there is additional overhead for the data file header information and
internal pointers. This overhead is usually fairly insignificant, consuming only a few
percent of the data file. However, there are some situations where this overhead can
become very significant. In particular, the overhead in storing burst data records in the
Burst History DataMode (see “Burst History” on page 164) can be very significant
when a small number of burst points (less than 100) is specified. Also, a large number
of short test runs can significantly add to the overhead required.
Different DataModes and data type compression modes require different amounts of
memory. The eDAQ
lite consumes raw data storage memory, excluding overhead, as
detailed in the following table.
NOTE
The Rainflow DataMode (see “Rainflow” on page 171) adds 4096 bytes of 32-bit float
data per channel for the rainflow stack size.
8.2 Common DataMode™ Parameters
ID
Unique identifier for the channel. This must conform to ID naming conventions. Valid
ID names:
• are case sensitive
• are limited to a maximum of 12 characters
DataMode Data Type Memory Consumption
Sequential 32-bit float 4 bytes per data point per channel
16-bit integer 2 bytes per data point per channel
8-bit integer 1 byte per data point per channel
Histogram 32-bit unsigned 4 bytes per bin per channel
HBM: public