Statistics - Agilent Technologies 3458A User Manual

60 ENTER 722;A
70 PRINT A
80 END
10 OUTPUT 722;"PRESET NORM"
20 OUTPUT 722;"ACV"
30 OUTPUT 722;"SETACV ANA"
40 OUTPUT 722;"MEM FIFO"
50 OUTPUT 722;"SMATH RES 8"
60 OUTPUT 722;"MMATH DBM"
70 OUTPUT 722;"TRIG SGL"
80 ENTER 722;A
85
90 PRINT A
100 END

Statistics

10 OPTION BASE 1
20 DIM Rdgs(20)
30 OUTPUT 722;"PRESET NORM"
40 OUTPUT 722"NRDGS 20"
50 OUTPUT 722;"MATH STAT"
60 ENTER
70 OUTPUT 722;"RMATH SDEV"
80 ENTER
90 PRINT S
100 END
122 Chapter 4 Making Measurements
For example, if the input voltage is 10V, the power is:
2
10 log (10 /8/1 mW)= 40.97dBm
·
10
The following program is similar to the preceding program except that it uses
the post-process DBM operation.
The STAT math operation performs five calculations on a group of readings
and stores the results in five math registers. The calculations are: standard
deviation, mean, number of samples, largest reading, and smallest reading.
Table 24 shows the STAT registers and their contents. You can read any of
the STAT registers using the RMATH command.
Register
SDEV
MEAN
NSAMP
UPPER
LOWER
The following program uses the real-time STAT operation to perform five
running calculations on 20 DC voltage readings. After the readings are taken
and transferred to the controller, the standard deviation is read and returned.
722 Rdgs(*)
722;S
The following program performs the post-process STAT operation on 20
readings stored in memory. The post,-process STAT operation is a batch
!SYN EVENT, ENTER DBM
!PRINT DBM
!PRESET, NRDGS 1,AUTO, DCV 10, TRIG SYN
!AC VOLTAGE MEASUREMENTS, AUTORANGE
!ANALOG ACV METHOD
!ENABLE READING MEMORY, FIFO MODE
!WRITE 8 TO RES REGISTER
!ENABLE POST-PROCESS DBM OPERATION
!TRIGGER READING
!RECALL READING USING IMPLIED READ,
!PERFORM DBM OPERATION
!PRINT DBM RESULT
Table 24: STAT Registers
Stored Result
Standard deviation
Average of the readings
Number of readings in this group of measurements
Largest reading in this group of measurements
Smallest reading in this group of measurements
!COMPUTER ARRAY NUMBERING STARTS AT 1
!DIMENSION ARRAY FOR 20 READINGS
!PRESET, NRDGS 1,AUTO, DCV 10, TRIG SYN
!20 READINGS PER TRIGGER
!ENABLE REAL-TIME STAT OPERATION
!SYN EVENT, ENTER READINGS
!READ STANDARD DEVIATION
!ENTER STANDARD DEVIATION
!PRINT STANDARD DEVIATION