HP 8920A Programmer's Manual page 292

Chapter 5, Advanced Operations
Status Reporting
292
Clearing the Event Register
The EVENT register is cleared whenever it is queried or whenever the Common
Command *CLS is sent to the Test Set.
Reading the Enable Register
Syntax
STATus:HARDware1:ENABle?
Example
OUTPUT 714;"STAT:HARD1:ENAB?"
ENTER 714;Register_value
Writing the Enable Register
Syntax
STATus:HARDware1:ENABle <integer>
Example
OUTPUT 714;"STAT:HARD1:ENAB 256"
Clearing the Enable Register
The ENABLE register is cleared by writing to it with an integer value of zero.