EXFO FTB-500 - Manual (Page 353)

Data Types
FTB-500 345
Applicable Data Types for Output —IEEE 488.2

This data type will be used by a device to return integer representations
in binary (base 2).
Examples: #B11011110101, #B110100, #B0100

This data type will be used by a device to return strings containing 7-bit
ASCII characters and especially when text has to be displayed since
even the non-printable characters are also returned.
Examples: "SCPI Commands", "SCPI ""Commands"""
# B
1
0
"
"
>
"
quote char>
"