Operation Theory
•
33
(PSC_Counter=3
)
Acquisition_in_progress
Scan_start
ADCONV
Acquired & stored data
(3 scans)
Operation start
Trigger
Delay until
Delay_Counter
reaches 0
Post Scan Count
3
2
1
0
Figure 17: Delay trigger
Note:
When the Delay_counter clock source is set to TIMEBASE, the
maximum delay time = 2
16
/40M s = 1.638ms, and when the source
is set to A/D sampling clock, the maximum delay time can be as
higher as (2
16
* SI_counter / 40M ).
Post-Trigger or Delay-trigger Acquisition with re-trigger
Use post-trigger or delay-trigger acquisition with re-trigger function in ap-
plications where you want to collect data after several trigger events. The
number of scans after each trigger is specified in PSC_counter, and users
could program
Retrig_no
to specify the re-trigger numbers. Fig 18 illus-
trates an example. In this example, 2 scans of data is acquired after the
first trigger signal, then the card waits for the re-trigger signal (re-trigger
signals which occur before the first 2 scans is completed will be i gnored).
When the re-trigger signal occurs, 2 more scan is performed. The process
repeats until specified amount of re-trigger signals are detected. The total
acquired data length = number of enable-channel * PSC_counter * Re-
trig_no.
