R&S FSMR, Operating Manual

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Status Reporting System R&S FSMR
1166.3363.12 5.32 E-1
Application of the Status Reporting Systems
In order to be able to effectively use the status reporting system, the information contained there must
be transmitted to the controller and further processed there. There are several methods which are
represented in the following. Detailed program examples are to be found in chapter 7, Program
Examples.
Service Request, Making Use of the Hierarchy Structure
Under certain circumstances, the instrument can send a service request (SRQ) to the controller. Usually
this service request initiates an interrupt at the controller, to which the control program can react with
corresponding actions. As evident from Fig. 5-4, an SRQ is always initiated if one or several of bits 2, 3,
4, 5 or 7 of the status byte are set and enabled in the SRE. Each of these bits combines the information
of a further register, the error queue or the output buffer. The corresponding setting of the ENABle parts
of the status registers can achieve that arbitrary bits in an arbitrary status register initiate an SRQ. In
order to make use of the possibilities of the service request, all bits should be set to "1" in enable
registers SRE and ESE.
Examples (cf. Fig. 5-4 and chapter 7, Program Examples, as well):
Use of command "*OPC" to generate an SRQ at the end of a sweep.
CALL IBWRT(analyzer%, "*ESE 1")
Set bit 0 in the ESE (Operation Complete)
CALL IBWRT(analyzer%, "*SRE 32")
Set bit 5 in the SRE (ESB)?
After its settings have been completed, the instrument generates an SRQ.
The SRQ is the only possibility for the instrument to become active on its own. Each controller program
should set the instrument in a way that a service request is initiated in the case of malfunction. The
program should react appropriately to the service request. A detailed example for a service request
routine is to be found in chapter 7, Program Examples.
Serial Poll
In a serial poll, just as with command "*STB", the status byte of an instrument is queried. However, the
query is realized via interface messages and is thus clearly faster. The serial-poll method has already
been defined in IEEE 488.1 and used to be the only standard possibility for different instruments to poll
the status byte. The method also works with instruments which do not adhere to SCPI or IEEE 488.2.
The VISUAL BASIC command for executing a serial poll is "IBRSP()". Serial poll is mainly used to
obtain a fast overview of the state of several instruments connected to the IEC bus.