Agilent Technologies 35670A Manual page 311

FORMat
FORM:DATA REAL selects definite or indefinite length block data for transfers to the analyzer but only
definite length block data for transfers from the analyzer. Data encoding is binary (the binary
floating-point format defined in the IEEE 754-1985 standard). The only allowed values for the second
parameter are 32 and 64; it determines how many bits are used for each number.
Note
It is easiest for Instrument BASIC to read numbers if the format is REAL, 64.
See "Data Formats" in the GPIB Programmer's Guide for more information.
9-3