EXFO IQS-600 Integrated Qualification System - Manual (Page 299)

IEEE 488.2 and Specific Commands
Integrated Qualification System 291
IEEE 488.2 Required Commands
*ESR?
Description The *ESR? query allows the programmer to
determine the current contents of the Standard
Event Status Register. Reading the Standard
Event Status Register clears it. See the contents of
this register below.
Syntax *ESR?
Parameter(s) None
Response Syntax
CME
MSB
PON DDE N.U OPC EXE QYE
LSB Standard Request Status Register
URQ