332 VT1422A Command Reference Chapter 7
[SENSe]
•The Current Value Table is an area in memory that can contain as many as 502
32-bit floating point values. Algorithms can copy any of their variable values
into these CVT elements while they execute. The algorithm statements to put
data into the CVT are:
writecvt( <expr>, <element_number> ) and
writeboth( <expr>, <element_number> ).
There is a fixed relationship between channel number and CVT element for
reading values from channels placed in the Scan List with ROUT:SEQ:DEF.
When mixing Scan List data acquisition with algorithm data storage, be careful
not to overwrite Scan List generated values with algorithm generated values.
See “ROUTe:SEQuence:DEFine” on page 323 for controlling CVT entries from
the analog scan list.
•Elements 0 through 9 are not accessible.
•The format of values returned is set using the FORMat[:DATA] command
•Returned Value: ASCII values are returned in the form ±1.234567E±123.
For example 13.325 volts would be +1.3325000E+001. Each value is followed
by a comma (,). A line feed (LF) and End-Or-Identify (EOI) follow the last value.
The data type is a string array.
REAL 32, REAL 64, and PACK 64, values are returned in the IEEE-488.2-1987
Definite Length Arbitrary Block Data format. This data return format is
explained in “Arbitrary Block Program and Response Data” on page233.
For REAL 32, each value is 4 bytes in length (the data type is a float32 array).
For REAL 64 and PACK 64, each value is 8 bytes in length (the data type is a
float64 array).
Note After *RST/Power-on, each element in the CVT contains the IEEE-754 value
"Not-a-number" (NaN). Elements specified in the DATA:CVT? command that have
not been written to be an algorithm will return the value 9.91E37.
•*RST Condition: All elements of CVT contains IEEE-754 "Not a Number."
•Use VXIplug&play function: hpe1422_readCVT_Q(...)
Usage SENS:DATA:CVT? (@10:511) Return all CVT values (502)
SENS:DATA:CVT? (@30:38) Return 9 values