Keysight Technologies DAQ970A Programming Manual page 152

2 SCPI Programming
*SRE <enable>
*SRE?
Service Request Enable Command and Query . Enable register for the
responding bits may generate a Request for Service (RQS) in the Status Byte. This RQS event may generate a "call
back" to your application as a type of asynchronous interrupt.
Parameter
Decimal sum of the bits in the register.
For example, to enable bit 2 (decimal value = 4), bit 3 (decimal value = 8), and
bit 7 (decimal value = 128), the decimal sum would be 140 (4 + 8 + 128).
Default: 0
Enables bit 4 (decimal value = 16) in the enable register: *SRE 16
– To enable specific bits, specify the decimal value corresponding to the binary-weighted sum of the bits in the
register. The selected bits are summarized in the "Master Summary" bit (bit 6) of the Status Byte Register. If any
of the selected bits change from 0 to 1, the instrument generates a Service Request signal.
– *CLS command clears the event register, but does not clear the enable register. An event register is a read-only
register that latches events from the condition register. While an event bit is set, subsequent events cor-
responding to that bit are ignored.
– Use *PSC to control whether the Status Byte enable register is cleared at power-on. For example, *PSC 0 pre-
serves the enable register contents through power cycles.
– The < enable > setting is non-volatile; it does not change after a Factory Reset
set (SYSTem:PRESet
*STB?
Read Status Byte Query . Queries the condition register for the
value equal to the binary-weighted sum of all bits set in the register. A condition register continuously monitors the
state of the instrument. Condition register bits are updated in real time; they are neither latched nor buffered.
Parameter
(none)
Reads the condition register when bits 3 and 5 are set: *STB?
– This query returns the same results as a Serial Poll but the "Master Summary" bit (bit 6) is not cleared if a Serial
Poll has occurred.
– Unlike how a reset clears the condition register, a factory reset (*RST) does not clear the Status Byte Register.
152
command), Status Preset
Typical return
+40
Status Byte
Typical return
+16
(STATus:PRESet command) or Clear Status
Status Byte Register
Keysight DAQ970A/DAQ973A Programming Guide
Register. Once enabled, the cor-
(*RST command) , Instrument Pre-
(*CLS command).
group and returns a decimal