Rohde & Schwarz 1065.6000.20, Operating Manual

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Messages FSE
1065.6016.12 5.8 E-16
Device Messages (Commands and Device Responses)
Device messages are transferred on the data lines of the IEC bus, the "ATN" control line not being
active. ASCII code is used. The device messages are more or less equal for the different interfaces.
A distinction is made according to the direction in which they are sent on the IEC bus:
– Commands are messages the controller sends to the instrument. They operate the device
functions and request informations.
The commands are subdivided according to two criteria::
1. According to the effect they have on the instrument:
Setting commands cause instrument settings such as reset of the
instrument or setting the center frequency.
Queries cause data to be provided for output on the IEC-bus,
e.g. for identification of the device or polling the
marker.
2. According to their definition in standard IEEE 488.2:
Common Commands are exactly defined as to their function and
notation in standard IEEE 488.2. They refer to
functions such as management of the standar-dized
status registers, reset and selftest.
Device-specific
commands
refer to functions depending on the features of the
instrument such as frequency setting. A majority of
these commands has also been standardized by the
SCPI committee (cf. Section 3.5.1).
– Device responses are messages the instrument sends to the controller after a query. They can
contain measurement results, instrument settings and information on the
instrument status (cf. Section 3.5.4).
Structure and syntax of the device messages are described in the following section. The commands are
listed and explained in detail in chapter 6.