Agilent Technologies Agilent E5250A User Manual
Page 219
Agilent E5250A User’s Guide, Edition 11
7-51
Command Reference
Status Byte Register
In general, use serial polling (not *STB?) inside interrupt service routines. Use
*STB? in other cases (not in interrupt service routine) when you want to know the
value of Status Byte.
Table 7-1
Status Byte Register of E5250A
Bit Definition
Explanation
0
Not Used.
Always zero.
1
Not Used.
Always zero.
2
Not Used.
Always zero.
3
Not Used.
Always zero.
4
Message Available
(MAV) Queue Summary
Message
Indicates whether Output Queue is empty. If
unread message exists, this bit is set to 1.
Otherwise, this bit is set to 0. Refer to
“Output Queue” on page 7-55.
5
Standard Event Status
Bit (ESB) Summary
Message
Indicates whether one or more of the enabled
Standard Events Status Register bits is set.
6
Request Service (RQS)
Message
Indicates whether a SRQ (Service Request)
has occurred. Read by Serial Poll.
Master Summary Status
(MSS) Summary
Message
Indicates that the instrument has at least one
reason for requesting service. Read by
*STB?.
7
Not Used.
Always zero.