HP HP VXI - Manuals

Programming the Status System 7 Chapter 2 Chapter 2 Programming the Status System About this Chapter This chapter discusses the structure of the status system used in SCPI instruments and explains how to program status registers. An important feature of SCPI instruments is that they all implement st...

10 Programming the Status System Chapter 2 Required Status Groups All SCPI instruments must implement a minimum set of status groups. Some instruments contain additional status groups, consistent with the general status register model. The minimum required status system is shown in Figure 2-3 . Figu...

Programming the Status System 11 Chapter 2 The Standard Operation Status and Questionable Data groups are 16 bits wide, while Status Byte and Standard Event groups are only 8 bits wide. In all 16 bit groups, the most significant bit (bit 15) is not used. Bit 15 always returns a zero. The commands th...

12 Programming the Status System Chapter 2 The meaning of each bit in the Status Byte is explained in the following table. Example commands using the Status Byte and Status Byte enable registers: * SRE 16 Generate an SRQ interrupt when messages are available. *SRE? Find out what events are enabled t...

Programming the Status System 13 Chapter 2 Example commands using Standard Event registers: *ESE 48 Generate a summary bit on execution or command errors. *ESE? Query the state of the Standard Event enable register. *ESR? Query the state of the Standard Event event register. Standard Operation Statu...

14 Programming the Status System Chapter 2 Questionable Data Group The Questionable Data status group provides information about the quality of instrument output and measurement data. Questionable Data is accessed through the STATus subsystem. As a beginner, you will rarely need to use this status g...

Programming the Status System 15 Chapter 2 Status System Programming Examples This section contains two example programs that use the status system and common commands to monitor when data is available from an instrument and when an error has occurred. Both programming examples are written in C and ...

16 Programming the Status System Chapter 2 • Define an SRQ handler to do the following: -- Read the Status Byte using ireadstb . ireadstb returns the RQS (request for service) bit in bit 6 of the status byte. After issuing a ireadstb, RQS is cleared indicating that the Service Request is being ackno...

18 Programming the Status System Chapter 2 iclose(id); } Using a Service Request to Detect Errors The following example program sets up an SRQ handler to be called when SCPI errors are detected using the Standard Event Status Register. The program then prompts for SCPI commands. If the SCPI command ...

Command Reference 23 Chapter 3 Chapter 3 Command Reference About this Chapter This section describes the SCPI status system and common (*) commands that can be used to program instruments in your mainframe.

24 Command Reference Chapter 3 STATus The STATus subsystem commands access the condition, event, and enable registers in the Operation Status Group and the Questionable Data Group. Subsystem Syntax STATus :OPERation :CONDition?:ENABle < event > :ENABle?[:EVENt]? :PRESet:QUEStionable :CONDition...

Command Reference 25 Chapter 3 :OPERation:ENABle? STATus:OPERation:ENABle? returns which bits in the event register (Operation Status Group) are unmasked. Comments • Reading the event register mask does not change the mask setting (STAT:OPER:ENAB <event>). • Related Commands: STAT:OPER:ENABle ...

28 Command Reference Chapter 3 Common Command Reference This section describes the IEEE-488.2 Common Commands that can be used to program instruments in the mainframe. Commands are listed alphabetically (the following table shows the Common Commands listed by functional group). For additional inform...