Math Registers; Null - Agilent Technologies 3458A User Manual

Math Registers

NULL

those two operations), send:
OUTPUT 722;"MATH CONT" !RE-ENABLES ONE REAL-TIME MATH OPERATION
OUTPUT 722;"MMATH CONT" !RE-ENABLES ONE POST-PROCESS MATH OPERATION
To re-enable two previously enabled math operations send:
OUTPUT 722;"MATH CONT,CONT" !RE-ENABLES TWO REAL-TIME MATH OPERATIONS
or
OUTPUT 722;"MMATH CONT,CONT" !RE-ENABLES TWO POST-PROCESS MATH
OPERATIONS
Table 23 shows the registers used by the real-time or post-process math
operations.
Table 23: Math Registers
Register Name
DEGREE
LOWER
MAX
MEAN
MIN
NSAMP
OFFSET
PERC
REF
RES
SCALE
SDEV
UPPER
PFAILNUM
You can write a value to any math register (except SDEV) using the SMATH
command. For example, to place the value of 22 in the DEGREE register,
send:
OUTPUT 722;"SMATH DEGREE,22"
You can read the value in any math register using the RMATH command.
For example, the following program reads and prints the value in the RES
register.
10 OUTPUT 722;"RMATH RES"
20 ENTER 722;A
30 PRINT A
40 END
The NULL operation subtracts a value from each reading (following the first
reading). The equation is:
or
Register Contents
Time constant for FILTER and RMS
Smallest reading in STATS
Upper limit for PFAIL operation
Average of readings in STATS
Lower limit for PFAIL
Number of samples in STATS
Subtrahend in NULL and SCALE
operations
Percent value for PERC operation
Reference value for DB operation
Reference impedance for DBM operation
Divisor in the SCALE operation
Standard deviation in STATS
Largest reading in STATS
The number of readings that passed
PFAIL before a failure was encountered
Chapter 4 Making Measurements 117