Agilent Technologies 8163A Programming Manual page 26

Introduction to Programming
*STB? returns the Status Byte Register
Status
Byte
All bits shown as
26
Figure 2 shows how the Standard Event Status Enable Mask (SESEM)
and the Standard Event Status Register (SESR) determine the Event
Status Bit (ESB) of the Status Byte.
OSB ESB QSB
7 6 5 4 3 2
0 1 0
are unused
Figure 2 The Event Status Bit
The SESR contains the information about events that are not slot
specific. For details of the function of each bit of the SESR, see
"Standard Event Status Register" on page 32.
The SESEM allows you to choose the event that may affect the ESB of
the Status Byte. If you set a bit of the SESEM to zero, the corresponding
event cannot affect the ESB. The default is for all the bits of the SESEM
to be set to 0.
The questionable and operation status systems set the Operational Status
Bit (OSB) and the Questionable Status Bit (QSB). These status systems
are described in "The Status Model" on page 27 and "Status Reporting –
The STATus Subsystem" on page 54.
N OT E
Unused bits in any of the registers change to 0 when you read them.
Agilent 8163A Lightwave Multimeter, Agilent 8164A Lightwave Measurement System,
& Agilent 8166A Lightwave Multichannel System, Third Edition
*ESE sets the Standard Event Status Enable Mask
Event
7 6
Status
1
Enable
Mask
&
1 0
&
7 6
Event
Status
0
Register
*ESR? returns the Standard Event Status Register
Common Commands
5 4 3 2 1 0
1 1 1 1 1
&
&
&
&
&
&
5 4 3 2 1 0
0 0 0 0 1