Status and Events
TDS 310, TDS 320 & TDS 350 Programmer Manual
3Ć7
When a bit in the SBR is set to one and the corresponding bit in the SRER is
enabled (6), the MSS bit in the SBR is set to one and a service request (GPIB
only) is generated (7).
Although most commands are completed almost immediately after being
received by the oscilloscope, some commands start a process that requires
more time. For example, once a HARDCOPY START command is executed, it
may be a few seconds before the hardcopy operation is complete. Rather
than remain idle while the operation is in process, the oscilloscope continues
processing other commands. This means that some operations are not
completed in the order that they were sent.
There may be times when the result of an operation is dependent on the
result of an earlier one, and you must be assured that the first operation has
completed before processing the next one. The status and event reporting
system provides ways to do this.
For example, a typical application would be to acquire a singleĆsequence
waveform, then take a measurement on the acquired waveform. You could
use the following command sequence:
/** Set up singleĆsequence acquisition **/
SELECT:CH1 ON
ACQUIRE:MODE SAMPLE
ACQUIRE:STOPAFTER SEQUENCE
/** Acquire waveform data **/
ACQUIRE:STATE ON
/** Set up the measurement parameters **/
MEASUREMENT:IMMED:TYPE AMPLITUDE
MEASUREMENT:IMMED:SOURCE CH1
/** Take amplitude measurement on acquired data **/
MEASUREMENT:IMMED:VALUE?
The acquisition of the waveform requires extended processing time and may
not complete before the amplitude measurement is taken (See Figure 3Ć7).
This will result in an incorrect amplitude value.
MEASUREMENT:IMMED:VALUE?
Processing Time
Acquiring Waveform Data
ACQUIRE:STATE ON
Figure 3Ć7:ăCommand Processing Without Using Synchronization
Synchronization
Methods