Stb - Keysight 8990B Programming Manual

2 IEEE-488 Command Reference

*STB?

The *STB? query reads the condition register of the Status Byte register and returns
a decimal value which corresponds to the binary-weighted sum of all bits set in the
register. The return format is <NR1> in the range of 0 to 255. This query is similar to
a Serial Poll, but it is processed like any other instrument command. This is a
read-only register, and the bits are not cleared when you read the register.
This query returns the same results as a Serial Poll, but the "Master Status
NOTE
Summary" (MSS) bit (bit 6) is not cleared if a Serial Poll has occurred.
The following table lists the bit definitions of the Status Byte register:
Table 2-4 Bit definitions: Status Byte register
Bit Weight/Decimal value
0 1
1 2
2 4
3 8
4 16
5 32
6 64
7 128
Refer to
Syntax
Example
*STB?
58
"Status Byte summary register"
?
*STB
Returns the bits currently set in the condition register.
Definition
Not used
Device Status register summary
Error/Event queue
Questionable Status register summary
Message available
Standard Event register summary
Master Status summary (Request for service)
Operation Status register summary
on page 39 for more details.
Keysight 8990B Programming Guide