Acqiris SA230E User Manual page 33

Descriptor Header Byte Descriptor Type
0x11
0x14
0x1f
Table 2.4 - List of header bytes used to identified the descriptor type.
In the descriptor stream, data are returned in block of 256 bits. An alignment descriptor (identified with
header 0x1f) is returned when needed to align when the processing has ended to a DDR4 word
boundary of 512 bits. This alignment block does not contain any usable information and shall be
ignored.
Pulse descriptors might not be stored in order and pulse descriptors from the previous record might be
stored after the trigger descriptor of the subsequent record. The record counter must be used to assign
pulse descriptors to the correct trigger descriptor.
The number of pulse descriptors per record depends on the number of pulses per record and therefore
on the input signal. Thus, the number of pulse descriptors per record is not constant and could also be
zero.
The following tables details the content of the trigger, pulse and alignment descriptors.
Bits Width
7:0 8
31:8 24
95:32 64
255:96 -
Table 2.5 - Structure of the trigger descriptor.
Acqiris SA230E User's Manual
Descriptor Size
Trigger 256 bits
Pulse 256 bits
Alignment (dummy) 256 bits
Field Type
Descriptor Type Unsigned
Record Counter Unsigned
Timestamp Unsigned
2.3 Real-time peak-listing mode (PKL option)
Comments
0x11 = trigger descriptor
Trigger position with resolution of 1/256
the sampling period
Reserved
th
of
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