Tektronix DSA8300, Руководство программиста

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Status and Events
The instrument provides a status and event reporting system for the GPIB
interfaces. This system informs you of certain signi
fi cant events that occur within
the instrument.
The instrument status handling system consists of fi ve 8-bit registers and two
queues for each interface. The remaining Status subtopics describe these registers
and components. They also explain how the event handling system operates.
Registers
The registers in the event handling system fall into two functional groups:
Status Registers contain information about the status of the instrument. They
include the Standard Event Status Register (SESR).
Enable Registers determine whether selected types of events are reported to
the Status Registers and the Event Queue. They include the Device Event
Status Enable Register (DESER), the Event Status Enable Register (ESER),
and the Service Request Enable Register (SRER).
Status
The Standard Event Status Register (SESR) and the Status Byte Register (SBR)
record certain types of events that may occur while the instrument is in use. IEEE
Std 488.2-1987 de
fi nes these registers.
Each bit in a Status Register records a particular type of event, such as an
execution error or message available. When an event of a given type occurs, the
instrument sets the bit that represents that type of event to a value of one. (You
can disable bits so that they ignore events and remain at zero. (See Registers).
Reading the status registers tells you what types of events have occurred.
The Standard Event Status Register (SESR). The SESR records eight types of
events that can occur within the instrument. Use the *ESR? query to read the
SESR register. Reading the register clears the bits of the register so that the
register can accumulate information about new events.
NOTE.
TekVISA applications use SESR bit 6 to respond to any of several events,
including some front panel actions.
DSA8300 Programmer Manual 3-1