Tektronix DSA8300, Programmer'S Manual

Page: 413 / 455

Status and Events
The acquisition of the waveform requires extended processing time. It may
not
fi nish before the instrument executes the CURVe? query (see the following
fi gure). This can result in incorrect curve values.
To ensure that the instrument completes waveform acquisition before attempting
to execute the CURVe? query, you can synchronize the program. The
fi gure
below shows the desired processing sequence.
You can use four commands to synchronize the operation of the instrument with
your application program: *WAI, BUSY?, *OPC, and *OPC?
*WAI
You can force commands to execute sequentially by using the *WAI command.
This command forces completion of the previous commands before processing
new ones.
The same command sequence using the *WAI command for synchronization
looks like this:
/** Sets up conditional acquisition **/
ACQUIRE:STATE OFF
SELECT:CH1 ON
HORIZONTAL:RECORDLENGTH 500
ACQUIRE:MODE SAMPLE
ACQUIRE:STOPAFTER COUNT 1
ACQUIRE:STOPAFTER:MODE CONDITION
/** Sets up the data preamble **/
DATA:START 1
DATA:STOP 500
DATA:ENCDG RIBINARY
/** Clear data and then acquire waveforms until
conditional stop occurs**/
ACQUIRE:DATA:CLEAR
ACQUIRE:STATE ON
/** Wait until the acquisition is complete before
querying the curve data**/
*WAI
/** Get the curve data **/
DSA8300 Programmer Manual 3-7