9.4 Configuring the Communications Protocol
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9
Use communications commands to set the measurement data transmission format to ASCII or
binary.
See: ":SYSTem:FORMat <ASCii/ BINary>" (p. 137)
This setting applies only to data sent in response to the following query messages:
•
:FETCh?
• :READ?
• :MEMory:DATA?
It also applies to data output sent by the measurement output functions.
Binary Data Format
Binary data is IEEE format single-precision (32-bit) floating-point values.
Binary data is sent in four-byte sequences beginning with the first byte (which includes the sign bit).
Responses to queries that return a single value, such as :FETCh?, consist of a measured value as four-byte
floating-point binary data. The delimiter is not sent.
Example
Transmit
:FETCh? + (terminator)
Receive (4-byte floating-point data)
Responses containing multiple values such as memory data consist of a continuous stream of binary data val-
ues with no punctuation or other separator between values.
Example
Transmit
:MEMory:DATA? + (terminator)
Receive (4-byte floating-point data) + (4-byte floating-point data) +.... + (4-byte floating-point data)
Select the Measurement Data Transmission Format (both RS-232C and
GP-IB)
1-Bit Sign
8-Bit Exponent
23-Bit Mantissa
First Byte Second Byte Third Byte Fourth Byte