Agilent Technologies E4406A VSA manual Status Byte Register, Programming Fundamentals, Chapter

Programming Fundamentals

Using the Instrument Status Registers

Status Byte Register

The RQS bit is read and reset by a serial poll. MSS (the same bit position) is read, non-destructively by the *STB? command. If you serial poll bit 6 it is read as RQS, but if you send *STB it reads bit 6 as MSS. For more information refer to IEEE 488.2 standards, section 11.

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