Keysight 8990B, Programming Manual

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2 IEEE-488 Command Reference
58 Keysight 8990B Programming Guide
*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.
The following table lists the bit definitions of the Status Byte register:
Table 2-4 Bit definitions: Status Byte register
Refer to “Status Byte summary register” on page 39 for more details.
Syntax
Example
NOTE
This query returns the same results as a Serial Poll, but the “Master Status
Summary” (MSS) bit (bit 6) is not cleared if a Serial Poll has occurred.
Bit Weight/Decimal value Definition
0 1 Not used
1 2 Device Status register summary
2 4 Error/Event queue
3 8 Questionable Status register summary
4 16 Message available
5 32 Standard Event register summary
6 64 Master Status summary (Request for service)
7 128 Operation Status register summary
*STB
?
*STB?
Returns the bits currently set in the condition register.