Teledyne SP Devices ADQ14, User Manual

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Classification Revision
Public PA1
Document ID Print date
18-2074 2018-04-06
Detection
window
Data
Padding
allowed
Record 1 Record 0
Record length Record length
Trigger level
Record 1 Record 0
Trailing edge window
Trigger level
Reset level
Trigger event inside TEW,
record is extended
Trailing edge window
Variable length mode Fixed length mode
Figure 6: Data collection mode 0 (raw pulse data).

Example
If the reduction factor is set to 5, every 5th record will be transferred to the host.
4.12.3 Pulse Metadata
In the pulse metadata mode, only the pulse metadata is transferred to the host. The individual metadata
fields are described in Section 4.8 and Fig. 7 presents how the mode acts on a stream of pulse data
with a detection window. The detection window trigger will generate a record which is populated with
metadata packets. If no pulses are detected during a detection window an empty metadata data packet
will be transferred to the host.
Table 6 describes the layout of the metadata packets. The byte column refers to the position in the
returned array. One record can consist of one or several metadata packets. The size of each metadata
packet is 8 bytes. Packets used for padding have all fields equal to zero and should be discarded.
Table 7 describes the format of the returned data for each record in pulse characterization mode.

Note
Invalid packets are identified by all fields being equal to zero.
The pulse metadata mode will pad the record with zero-filled metadata packets if the total amount of data
during one detection window is less than the specified the minimum frame length.
Table 6: The metadata packet structure.
Field Byte Size Format
Pulse peak timestamp 3:0 4 bytes 32-bits unsigned integer
Pulse peak value 5:4 2 bytes 16-bits signed integer
Pulse width 7:6 2 bytes 16-bits unsigned integer
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