Rohde & Schwarz ESW Series, User Manual

Page: 381 / 759

Network and Remote Operation
R&S
®
ESW
381 User Manual 1177.6298.02 ─ 08
● Status Byte (STB) and Service Request Enable Register (SRE) ..........................381
● IST Flag and Parallel Poll Enable Register (PPE) ................................................ 382
● Event Status Register (ESR) and Event Status Enable Register (ESE) ...............382
● STATus:OPERation Register ................................................................................ 383
● STATus:QUEStionable Register ............................................................................384
● STATus:QUEStionable:ACPLimit Register ............................................................385
● STATus:QUEStionable:EXTended Register .......................................................... 386
● STATus:QUEStionable:EXTended:INFO Register ................................................ 386
● STATus:QUEStionable:FREQuency Register ....................................................... 387
● STATus:QUEStionable:LIMit Register ...................................................................388
● STATus:QUEStionable:LMARgin Register ............................................................388
● STATus:QUEStionable:POWer Register ...............................................................389
● STATus:QUEStionable:TIMe Register .................................................................. 390
● STATus:QUEStionable:TRANsducer Register ...................................................... 390
Status Byte (STB) and Service Request Enable Register (SRE)
The
STatus Byte
(STB) is already defined in IEEE 488.2. It provides a rough over-
view of the instrument status by collecting the pieces of information of the lower regis-
ters. A special feature is that bit 6 acts as the sum bit of the remaining bits of the status
byte.
The STB can thus be compared with the
CONDition
part of an SCPI register and
assumes the highest level within the SCPI hierarchy.
The STB is read using the command
*STB?
or a serial poll.
The
STatus Byte
(STB) is linked to the
Service Request Enable
(SRE) register.
Each bit of the STB is assigned a bit in the SRE. Bit 6 of the SRE is ignored. If a bit is
set in the SRE and the associated bit in the STB changes from 0 to 1, a service
request (SRQ) is generated. The SRE can be set using the command
*SRE
and read
using the command
*SRE?
.
Table 14-7: Meaning of the bits used in the status byte
Bit No. Meaning
0...1 Not used
2 Error Queue not empty
The bit is set when an entry is made in the error queue. If this bit is enabled by the SRE, each
entry of the error queue generates a service request. Thus an error can be recognized and
specified in greater detail by polling the error queue. The poll provides an informative error mes-
sage. This procedure is to be recommended since it considerably reduces the problems
involved with remote control.
3 QUEStionable status register summary bit
The bit is set if an
EVENt
bit is set in the
QUEStionable
status register and the associated
ENABle
bit is set to 1. A set bit indicates a questionable instrument status, which can be speci-
fied in greater detail by querying the
STATus:QUEStionable
status register.
4 MAV bit (message available)
The bit is set if a message is available in the output queue which can be read. This bit can be
used to enable data to be automatically read from the instrument to the controller.
Remote Control Basics