BNC 845-M - Manual (Page 15)

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Model 845-M Programmer’s Manual V1.1 2011
:SYSTem
:TRIGger
:UNIT
All Model 845-M SCPI commands, except the :ABORt command, have one or more subcommands
(keywords) associated with them to further define the instrument function to be controlled. The
subcommand keywords may also have one or more associated subcommands (keywords). Each
subcommand level adds another layer to the command tree. The command keyword and its associated
subcommand keywords form a portion of the command tree called a command subsystem.
Status System Programming
The Model 845-M implements the status byte register, the Service Request Enable Register, the
Standard Event Status Register, and the Standard Event Status Enable Register.
The Model 845-M status system consists of the following SCPI-defined status reporting structures:
x The Instrument Summary Status Byte
x The Standard Event Status Group
x The Operation Status Group
x The Questionable Status Group
The following paragraphs describe the registers that make up a status group and explain the status
information that each status group provides.
Status Registers
In general, a status group consists of a condition register, a transition filter, an event register, and an
enable register. Each component is briefly described in the following paragraphs.
Condition Register
The condition register is continuously updated to reflect the current status of the Model 845-M. There
is no latching or buffering for this register, it is updated in real time. Reading the contents of a
condition register does not change its contents.