Keysight Technologies 3458A Guide D'utilisation page 181

program determines the percent error of a 10 VDC voltage measurement. Line 60
enters the ideal value (10) into the PERC register. Line 70 triggers the 20 readings.
If a reading is exactly 10 VDC, the value returned is 0. If a reading is, for example,
10.1 VDC, the value returned is:
10 OPTION BASE 1!COMPUTER ARRAY NUMBERING STARTS AT 1
20 DIM Perc(20)!DIMENSION ARRAY FOR 20 PRECENTAGES
30 OUTPUT 722;"PRESET NORM"!PRESET, NRDGS 1,AUTO, DCV 10, TRIG SYN
40 OUTPUT 722;"NRDGS 20"!20 READINGS PER TRIGGER
50 OUTPUT 722;"MATH PERC"!ENABLE REAL-TIME PERC OPERATION
60 OUTPUT 722;"SMATH PERC 10"!WRITE 10 TO PERC REGISTER
70 ENTER 722;Perc(*)!SYN EVENT, ENTER PERCENT DIFFERENCE
80 PRINT Perc(*)!PRINT PERCENT DIFFERENCE
90 END
The following program is similar to the preceding program except that it uses the
post-process PERC operation.
10
20
30
40
50
60
70
80
90
95 !PERFORM PERC OPERATION
100 PRINT Perc(*)!PRINT PERCENT DIFFERENCE
110 END
DB
The DB math operation calculates a ratio in decibels. The equation is:
You can change the value in the REF register using the SMATH command.
Keysight 3458A User's Guide
Result = ((10.1 - 10)/10)@100 = 0.01@100 = 1
OPTION BASE 1!COMPUTER ARRAY NUMBERING STARTS AT 1
DIM Perc(20)!DIMENSION ARRAY FOR 20 PERCENTAGES
OUTPUT 722;"PRESET NORM"!PRESET,NRDGS 1,AUTO, DCV 10, TRIG SYN
OUTPUT 722;"MEM FIFO"!ENABLE READING MEMORY, FIFO MODE
OUTPUT 722;"NRDGS 20"!20 READINGS PER TRIGGER
OUTPUT 722;"MMATH PERC"!ENABLE POST-PROCESS PERC OPERATION
OUTPUT 722;"SMATH PERC 10"!WRITE 10 TO PERC REGISTER
OUTPUT 722;"TRIG SGL"!TRIGGER READINGS
ENTER 722;Perc(*)!RECALL READINGS USING IMPLIED READ,
Result = 20@log ,(Reading/REF)
10
Where:
Reading is any reading.
REF is the value in the REF register (default = 1).
Making Measurements 4
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