R&S ZNB Series User Manual page 836

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R&S ZNB/ZNBT
6.5.4 Application of the status reporting system
The purpose of the status reporting system is to monitor the status of one or several
devices in a measuring system. To do this and react appropriately, the controller must
receive and evaluate the information of all devices. The following standard methods
described in the following sections are used:
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Service request (SRQ) initiated by the measuring device
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Serial poll of all devices in the bus system, initiated by the controller to find out who
sent an SRQ and why
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Parallel poll of all devices
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Query of a specific instrument status by commands
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Query of the error queue
6.5.4.1 Service request
The R&S ZNB/ZNBT can send a service request (SRQ) to the controller. Usually this
service request causes an interrupt, to which the control program can react appropri-
ately.
Initiating an SRQ
As shown in section
of bits 2, 3, 4, 5 or 7 of the status byte are set and enabled in the SRE. Each of these
bits summarizes the information of a further register, the error queue or the output buf-
fer.
The ENABle parts of the status registers can be set such that arbitrary bits in an arbi-
trary status register initiate an SRQ. To use the possibilities of the service request
effectively, all bits in the enable registers SRE and ESE must be set to "1".
Example: Use *OPC to generate an SRQ
1. Set bit 0 in the ESE (Operation Complete).
2. Set bit 5 in the SRE (ESB).
3. Insert *OPC in the command sequence (e.g. at the end of a sweep).
When all commands preceding *OPC have been completed, the instrument generates
an SRQ.
Example: Generate an SRQ when a limit is exceeded
1. Set bit 3 in the SRE (summary bit of the STATus:QUEStionable register, set
after STATus:PRESet)
2. Set bit 10 in the STATus:QUEStionable:ENABle register (summary bit of the
STATus:QUEStionable:LIMit1 register)
3. Set bit 1 in the STATus:QUEStionable:LIMit1:ENABle register
User Manual 1173.9163.02 ─ 62
Overview of status registers, an SRQ is initiated if one or several
Remote control
Status reporting system
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