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APPENDIX B 53
of the first data sample in each retrieved data record. The time of trigger event is returned in the
AdditionalData parameter.
Timestamp Source Timestamp value Resolution
System (IEEE 1588) PTP or TAI (International Atomic Time) 20 ns
PXIe_CLK100 Elapsed time from last SYNC 20 ns
PXI_CLK10 Elapsed time from last SYNC 100 ns
Table 4-3: Timestamp Source and Resolution
A
DDITIONAL
D
ATA
The additional information associated with the data records are returned as a JSON (Java Script
Object Notation) array of name/value pairs:
[[JSON array for channel 1 ’s first record ], [JSON array for channel
2 ’s first record], ….]
The JSON object array for each channel is:
[{Object1}, {Object2} , …]
Each object is a list of name/value pairs:
{name1:value1, name2: value2 ,…}
JSON objects can be parsed using the following defined name strings.
Object Name String Value
Over range Over-Range True when any overload status bit is set.
Trigger time Trigger Timestamp
Seconds The trigger timestamp in seconds
Trigger Timestamp
Fraction The fraction portion of trigger timestamp.
Dropped trigger timestamp_sec The timestamp of when the trigger would have
occurred.
timestamp_frac The fraction portion.
Trigger Dropped The channel name of the lost trigger.
Table 4-4: Additional Data JSON Names and Values