8-4
Data Store
Average
The average mode displays the mean (average) of all measured readings stored in the buffer.
The following equation is used to calculate mean:
where:
y is the average.
X
i
is a stored reading.
n is the number of stored readings.
Standard deviation
This mode displays the standard deviation of buffered readings. The following equation is
used to calculate standard deviation:
where:
y is the average.
X
i
is a stored reading.
n is the number of stored readings.
Timestamp format
Buffer readings can be recalled using the absolute timestamp format or the delta format. For
the absolute format, readings are referenced to zero seconds. For the delta format, the times-
tamp indicates the time between the displayed reading and the previous reading.
Perform the following steps to set the timestamp format:
1.
While in the normal display mode, press CONFIG and then STORE to display the
timestamp choices.
2.
Place the cursor on ABSOLUTE or DELTA and press ENTER.
Timestamp accuracy
Because of internal timing methods, the timestamp value is only approximate. The method
in which the timestamp is implemented limits its use in time-critical applications. If accurate
test timing is crucial, it is recommended that an external timer be used in conjunction with the
SourceMeter.
y
X
i
i
1
=
n
∑
n
---------------
=
y
X
i
2
i
n 1
–
=
n
∑
1
n
---
X
i
i
1
=
n
∑
2
–
n
1
–
---------------------------------------------------------------
=
Summary of Contents for 6430
Page 26: ......
Page 32: ......
Page 78: ...2 14 Connections ...
Page 98: ...3 20 Basic Source Measure Operation ...
Page 138: ...5 30 Source Measure Concepts ...
Page 156: ...6 18 Range Digits Speed and Filters ...
Page 168: ...7 12 Relative and Math ...
Page 176: ...8 8 Data Store ...
Page 202: ...9 26 Sweep Operation ...
Page 248: ...11 22 Limit Testing ...
Page 310: ...16 6 SCPI Signal Oriented Measurement Commands ...
Page 418: ...17 108 SCPI Command Reference ...
Page 450: ...18 32 Performance Verification ...
Page 477: ...A Specifications ...
Page 489: ...B StatusandErrorMessages ...
Page 498: ...B 10 Status and Error Messages ...
Page 499: ...C DataFlow ...
Page 503: ...D IEEE 488BusOverview ...
Page 518: ...D 16 IEEE 488 Bus Overview ...
Page 519: ...E IEEE 488andSCPI ConformanceInformation ...
Page 523: ...F MeasurementConsiderations ...
Page 539: ...G GPIB488 1Protocol ...
Page 557: ......