Rohde & Schwarz EX-IQ-BOX, Руководство пользователя

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Remote Control Basics
R&S
®
EX-IQ-BOX
234 User Manual 1409.5570.32 ─ 05
Event Status Register (ESE)
1. Set the OPC mask bit (bit no. 0) in the ESE:
*ESE 1
2. Send the overlapped command without
*OPC
,
*OPC?
or
*WAI
3. Poll the operation complete state periodically (by means of a timer) using the
sequence:
*OPC
;
*ESR?
A return value (LSB) of 1 indicates that the overlapped command has finished.
*OPC? with short timeout
1. Send the overlapped command without
*OPC
,
*OPC?
or
*WAI
2. Poll the operation complete state periodically (by means of a timer) using the
sequence: <short timeout>;
*OPC?
3. A return value (LSB) of 1 indicates that the overlapped command has finished. In
case of a timeout, the operation is ongoing.
4. Reset timeout to former value
5. Clear the error queue with
SYStem:ERRor?
to remove the "-410, Query interrupted"
entries.
Using several threads in the controller application
As an alternative, provided the programming environment of the controller application
supports threads, separate threads can be used for the application GUI and for controlling
the instrument(s) via SCPI.
A thread waiting for a
*OPC?
thus will not block the GUI or the communication with other
instruments.
8.4 General Programming Recommendations
Initial instrument status before changing settings
Manual operation is designed for maximum possible operating convenience. In contrast,
the priority of remote control is the "predictability" of the instrument status. Thus, when a
command attempts to define incompatible settings, the command is ignored and the
instrument status remains unchanged, i.e. other settings are not automatically adapted.
Therefore, control programs should always define an initial instrument status (e.g. using
the *RST command) and then implement the required settings.
Command sequence
As a general rule, send commands and queries in different program messages. Other-
wise, the result of the query may vary depending on which operation is performed first
(see also Preventing Overlapping Execution).
General Programming Recommendations