Agilent Technologies E2730A, Installation And Operation Manual

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E2730A VXI RF TUNER
3-4 OPERATION
3.3.4 E2730A COMMUNICATION PROTOCOL
The operation of the E2730A is normally controlled using word serial
commands (refer to the VXIbus Specification, paragraph C.3.3.1) and
IEEE-488.2 modeled ASCII mnemonics. The Tuner also supports register
based VXI operations. Each communication method is discussed in the
following paragraphs.
WORD SERIAL
IEEE-488.2 COMMANDS
COMMAND MESSAGE
FORMAT
The word serial command messages used with the E2730A consist
exclusively of ASCII-encoded data. Command headers consist of
three-character mnemonics, which are defined in the command tables
provided in this section. Headers are case independent and may be entered
in upper or lower case letters. IEEE 488.2 Communication commands
must be prefixed with an "*" character as shown in the Communication
Message Command Table. All queries must be suffixed with the "?"
character. The command parser ignores all "white space" (ASCII 0
through 20 hex, with exceptions being communication protocol
characters). The parser accepts numeric arguments in the forgiving
numeric representation form (described below). Multiple commands must
be separated by the ";" character. Multiple arguments of a single
command must be delimited with "," character(s). Message strings sent to
the tuner must be terminated with a linefeed (0A hex) character or VXI
(END).
COMMAND MESSAGE
PROCESSING
All command message data is stored in the input buffer until a valid
message termination is received. The message is then parsed and
executed. Additional command message data may be sent to the unit
within the boundaries of the input buffer.
The command message format is checked for validity as the message is
parsed and executed. If the command message fails to meet the
restrictions of the command message format, then an error is generated in
an Event Status Register, and the rest of the message is processed
normally.
QUERY RESPONSE
FORMAT
Query responses maintain a fixed field format. Query responses begin
with the mnemonic in upper case letters. Responses containing numeric
arguments separate the first argument and the mnemonic with a space