Agilent Technologies PSA Series User And Programming Manual page 360

Using the STATus System
Using the Status Registers
The standard event status register is used to determine the specific
event that set bit 5 in the status byte register. To query the standard
event status register, send the command *ESR?. The response will be
the decimal sum of the bits which are enabled (set to 1). For example, if
bit number 7 and bit number 3 are enabled, the decimal sum of the 2
bits is 128 plus 8. So the decimal value 136 is returned.
In addition to the standard event status register, the standard event
status group also contains a standard event status enable register. This
register lets you choose which bits in the standard event status register
will set the summary bit (bit 5 of the status byte register) to 1. Send the
*ESE <number> command where <number> is the sum of the decimal
values of the bits you want to enable. For example, to enable bit 7 and
bit 6 so that whenever either of those bits is set to 1, the standard event
status summary bit of the status byte register will be set to 1, send the
command *ESE 192 (128 + 64). The command *ESE? returns the
decimal value of the sum of the bits previously enabled with the *ESE
<number> command.
The standard event status enable register presets to zeros (0).
360 Chapter 6