Operation Theory
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Acquisition_in_progress
Scan_start
ADCONV
(M_counter = M = 3, PSC_counter=0)
Acquired data
Acquired & stored data
(M samples)
Operation start
Trigger
Data acquisition
won’t stop until
this conversion
completes
Trigger occurs
Figure 11: Pre-trigger scan acquisition (trigger occurs when a
conversion is in progress)
When the trigger signal occurs before the first M scans of data are con-
verted, the amount of stored data could be fewer than the originally speci-
fied amount M_counter, as illustrated in figure 12. This situation can be
avoided by setting
M_enable.
If
M_enable
is set to 1, the trigger signal will
be ignored until the first M scans of data are converted, and it assures the
user M scans of data under pre-trigger mode, as illustrated in figure 13.
However, if
M_enable
is set to 0, the trigger signal will be accepted any
time, as illustrated in figure 12. Note that the total amount of stored data will
always be equal to the number in the M_counter because the data acqui-
sition won’t stop until a scan is completed.
Acquisition_in_progress
Scan_start
AD_conversion
(M_Counter = M = 3, PSC_Counter=0)
Acquired & stored data
(2 scans)
Operation start
Trigger
Figure 12: Pre-trigger with M_enable = 0 (Trigger occurs before M
scans)
