FLIR Lepton 1.5, Инженерная спецификация

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FLIR LEPTON® Engineering Datasheet
The information contained herein does not contain technology as defined by the EAR, 15 CFR 772, is publicly available,
and therefore, not subject to EAR. NSR (6/14/2018).
Information on this page is subject to change without notice.
Lepton Engineering Datasheet, Document Number: 500-0659-00-09 Rev: 203
60
with US export restrictions. For each unique frame, two partial and invalid frames follow in the VoSPI stream. This
pattern is illustrated in
Figure 37
, with unique frames shown in blue and invalid frames shown in gray. The 32-bit
frame counter provided in the telemetry lines (see
Telemetry Modes, page 23
) only increments on new frames,
which is also illustrated in
Figure 37
. The segment numbers will follow accordingly: 1, 2, 3, 4, 0, 0, 0, 0, 0, 0, 0, 0,
1, 2, 3, 4, etc., where unique frames are comprised of segment numbers 1, 2, 3, 4 and invalid frames are
comprised of zeros for each segment number.
Figure 37 - Frame Counter for Successive Frames
NOTE: Blue frames are different than the previous frames, gray frames are invalid.
4.2.3.3.1 Establishing/Re-Establishing Sync
The basic process for establishing synchronization is listed below:
•
Deassert /CS and idle SCK for at least 5 frame periods (>185 msec). This step ensures a timeout of the
VoSPI interface, which puts the Lepton 3 in the proper state to establish (or re-establish) synchronization.
•
Assert /CS and enable SCLK. This action causes the Lepton 3 to start transmission of a first packet.
•
Examine the ID field of the packet, identifying a discard packet. Read out the entire packet.