Rohde & Schwarz 1145.1010.04/05/06, Operating Manual

Page: 452 / 813

Status Reporting System R&S
®
ZVA/ZVB/ZVT
1145.1084.12 5.20 E-1
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EVENt
The EVENt part indicates whether an event has occurred since the last reading, it is the
"memory" of the condition part. It only indicates events passed on by the transition filters. It is
permanently updated by the instrument. This part can only be read by the user. Reading the
register clears it. This part is often equated with the entire register.
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ENABle
The ENABle part determines whether the associated EVENt bit contributes to the sum bit (cf.
below). Each bit of the EVENt part is ANDed with the associated ENABle bit (symbol '&'). The
results of all logical operations of this part are passed on to the sum bit via an OR function
(symbol '+').
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ENAB bit =0: The associated EVENt bit does not contribute to the sum bit.
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ENAB bit =1: If the associated EVENT bit is "1", the sum bit is set to "1" as well.
This part can be overwritten and read by the user at will. Its contents are not affected by
reading.
As shown in the graphical overview, the status information is of hierarchical structure.
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STB, SRE The register STatus Byte (STB) defined in IEEE 488.2 and its associated mask
register Service Request Enable (SRE) form the highest level of the status reporting system.
The STB provides a rough overview of the instrument status, collecting the information of the
lower-level registers.
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ESR, SCPI registers
The STB receives its information from the following registers:
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The standard IEEE 488.2 Event Status Register (ESR) with the associated mask register
standard event status enable (ESE).
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The STATus:OPERation and STATus:QUEStionable registers which are defined by SCPI and
contain detailed information on the instrument.
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IST, PPE The IST flag ("Individual STatus"), like the SRQ, combines the entire instrument
status in a single bit. The PPE is associated to the IST flag. It fulfills an analogous function for
the IST flag as the SRE does for the service request.
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Output buffer contains the messages the instrument returns to the controller. It is not part of the
status reporting system but determines the value of the MAV bit in the STB and thus is
represented in the overview.
The sum bit is obtained from the EVENt and ENABle part for each register. The result is then entered
into a bit of the CONDition part of the higher-order register.
The instrument automatically generates the sum bit for each register. Thus an event can lead to a
service request throughout all levels of the hierarchy.
Contents of the Status Registers
The individual status registers are used to report different classes of instrument states or errors. The
following status registers belong to the general model described in IEEE 488.2:
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The STatus Byte (STB) gives a rough overview of the instrument status.
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The IST flag combines the entire status information into a single bit that can be queried in a
parallel poll.
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The Event Status Register (ESR) indicates general instrument states.