SCPI Commands for Digital Interfaces
TM-XDOP-01XN 4–55
Status Byte
The Status byte register contains the STB and RQS(MSS) messages as defined in
488.1. The user can read the status byte register using a 488.1 serial poll or the
488.2 *STB? common command. If the user sends a serial poll, bit 6 will respond
with Request Service (RSQ). The value of the status byte is not altered by a serial
poll.
The *STB? query causes the device to send the contents of the Status Byte
Register and the Master Summary Status (MSS) summary message. The *STB?
query does not alter the status byte, MSS, or RQS.
Table 4-20
Standard Event Status Register
Bit Bit Weight Bit Name Description
0 1 Operation Complete
(OPC)
Set if KOPC command has been received and all pending
operations have been completed. The message, Event –800
Operation Complete, is loaded into the Error/Event Queue.
1 2 Request Control
(RQC)
Not implemented. Always set to 0.
24 Query Error
(QYE)
Set if an attempt is being made to read data from the output queue
when no output is either present or pending. Suggests that data in
the output queue has been lost. See “Query Error List” on page D–
6 for possible error codes.
3 8 Device Dependent
Error
(DDE)
Set if there is a device-specific error. See “Device-Specific Error
List” on page D–5 for possible error codes.
4 16 Execution Error
(EXE)
Set if a program data element, following a header, was evaluated
by the power supply as outside of its legal input range, or is
otherwise inconsistent with the power supply’s capabilities.
Suggests that a valid program message could not be properly
executed due to some power supply condition. See “Execution
Error List” on page D–3 for possible error codes.
5 32 Command Error
(CME)
Set if an IEEE488.2 syntax error has been detected by the parser,
an unrecognized header was received, or a group Execute Trigger
was entered into the input buffer inside an IEEE 488.2 program
message. See “Command Error List” on page D–2 for possible
error codes.
6 64 User Request
(URQ)
Set if the bit is unmasked and the instrument wishes to support a
488.2 user request event. An event occurs when the instrument
detects the activation of a user request local control. The message,
Event –600 User Request, is loaded into the Error/Event Queue.
7 128 Power ON
(PON)
Not implemented
8–
15
Reserved Reserved for possible future use by IEEE. Bit values are reported
as zero.
TM-XDOP-01XN.book Page 55 Monday, July 17, 2006 11:19 AM