"Cls - HP 1652B Programming Reference Manual

Command Syntax:
Example:
Note u
HP 1652Bll6536
(Clear Status)
The *CLS common command clears the status data structures, including
the device defined error queue. If the l CLS command immediately
follows a <terminator > , the output queue and the MAV (Message
Available) bit will be cleared.
'CLS
OUTPUT XXX;"*CLS"
Refer to appendix B, "Status Reporting," for a complete discussion of
status.
command
Common Commands