Specifications

564 Appendix B
GPIB Status Report System
Status Register Structure
When the *CLS command is executed, each bit in the Standard Event Status Register is
cleared.
Table B-2 Status Bit Definition of Standard Event Status Register
Bit
position
Name Description
0 Operation Compete bit Set to 1 upon completion of all operations done by
commands that proceed the
*OPC? command.
1 Not used Always 0.
2 Query Error Bit 1. Set to 1 when the E4991A has no transferred data in
the output queue in spite of a Query request.
2. Set to 1 when transferred data in the E4991A output
queue have been lost because of an incoming new
message.
3 Device Dependent Error Bit Set to 1 when an error other than command errors, Query
errors, and execution errors has occurred.
4 Execution Error 1. Set to 1 when a specified parameter in a GPIB
command is out of range or cannot be processed by
the E4991A.
2. Set to 1 when a GPIB command cannot be executed
correctly because of the E4991A’s state.
5 Command Error Bit 1. Set to 1 when an IEEE 488.2 syntax error has
occurred (a command sent to E4991A does not
conform to the syntax stipulated by the IEEE 488.2
standard). Possible reasons are that a command
parameter does not conform to the E4991A listen
format or it is of a type E4991A cannot accept.
2. Set to 1 when a semantic error has occurred. Possible
reasons are that a command sent to the E4991A has a
misspelling or is an IEEE 488.2 command that
E4991A cannot process.
3. Set to 1 when GET (Group Execution Trigger) is
input to a program input buffer.
6 Not used Always 0
7 Power ON Bit Set to 1 when the E4991A is powered on.