Agilent Technologies Agilent E5250A User Manual page 219

Table 7-1
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.
Status Byte Register of E5250A
Bit Definition
0 Not Used.
1 Not Used.
2 Not Used.
3 Not Used.
4 Message Available
(MAV) Queue Summary
Message
5 Standard Event Status
Bit (ESB) Summary
Message
6 Request Service (RQS)
Message
Master Summary Status
(MSS) Summary
Message
7 Not Used.
Agilent E5250A User's Guide, Edition 11
Explanation
Always zero.
Always zero.
Always zero.
Always zero.
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.
Indicates whether one or more of the enabled
Standard Events Status Register bits is set.
Indicates whether a SRQ (Service Request)
has occurred. Read by Serial Poll.
Indicates that the instrument has at least one
reason for requesting service. Read by
*STB?.
Always zero.
Command Reference
Status Byte Register
7-51