Tau Digital Data Channel - FLIR TAU User Manual

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Tau Digital Data Channel

Tau provides a digital data channel that outputs the camera's data in a digital format. This
channel can be used in conjunction with commercially-available digital frame grabbers, digital
displays, or custom receive electronics. It can also be used with FLIR's Ethernet Adapter. For
Tau users with embedded or specialty applications that require custom control software, a
Software Developer's Kit (SDK) is available to support your development efforts. The SDK
accessory is described in the Accessories portion of this User's Manual. Using the Digital Data
Channel is an advanced regime that should only be attempted by qualified customers. The
Appendices contain details for the Digital Data Channel.
The digital data channel can be configured to output 14-bit data after application of calibration
(Non Uniformity Correction or NUC) terms. This mode is most useful for external signal-
processing and/or analysis of the camera output. The digital channel can also be configured to
provide 8-bit data after application of video processing algorithms (e.g. 'Automatic' AGC mode,
white-hot/black-hot polarity, image orientation, DDE filtered, and on-screen symbols). The 8-bit
data is essentially a digital version of the video stream provided on the analog video channel and
is therefore more appropriate than the 14-bit data for interfacing to a digital display.
The digital data channel employs serial low-voltage differential signaling (LVDS). The channel
consists of three signal lines—a clock, a composite sync (frame sync and data valid), and serial
data. This is a modern high speed interface employing a twisted pair current loop architecture.
National Semiconductor offers a good introduction and overview in the following document:
http://www.national.com/appinfo/lvds/files/lvds_ch1.pdf
A serial-in-parallel-out (SIPO) module is available from FLIR for converting the serial data to 14-
bit parallel LVDS output (plus frame sync, line sync, and pixel clock). The parallel data can be
captured using a frame-grabber board installed in a PC.
One frame grabber possibility is the National Instruments IMAQ PCI-1422 board using digital
interface cable part number 308-0013-00. Another frame grabber option is the Bit Flow
RoadRunner Model 14-M board using digital interface cable part number 308-0016-00-03.
Both of these computer-based frame grabber boards require third-party software not offered
or supported by FLIR.
FLIR supplies camera setup files for both the IMAQ and Bit Flow frame grabber boards, but
FLIR does not formally support their use, nor do we claim or guarantee that these setup files
will be suitable for any particular use or application.
Refer to http://www.corebyindigo.com/service/softwareupdates.cfm
TAU-0035-00-10, version 100 April 2009 4-1