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Chapter 2 Hardware Overview
NI PXI/PCI-1409 User Manual 2-4 ni.com
Acquisition and Region-of-Interest (ROI) Control
The acquisition and region-of-interest control circuitry routes the active
pixels from the 10-bit ADC to the onboard memory. The NI 1409 can
perform ROI and scaling on all video lines. Pixel and line scaling transfers
certain multiples (two, four, or eight) of pixels and lines to onboard
memory.
RTSI Bus
The seven trigger lines on the RTSI bus provide a flexible interconnection
scheme between multiple image acquisition devices, as well as between
National Instruments DAQ or Motion Control devices.
Digital Input/Output Circuitry
The digital input/output (I/O) circuitry routes, monitors, and drives the
external trigger lines, RTSI bus lines, and camera control lines. You can
use the trigger lines to start or stop an acquisition on a rising or falling
edge. You also can map onboard signals such as HSYNC, VSYNC,
ACQUISTION_IN_PROGRESS, and ACQUISITION_DONE to these
lines. The camera control lines provide a means to generate deterministic
signals for triggering cameras, strobe lights, or other timing-critical
applications. This module also contains an external clock generation circuit
you can use as the source clock for a line scan camera.
Note The NI 1409 does not support pixel clock output on the trigger lines.
Acquisition Modes
The NI 1409 supports the following five video acquisition modes:
• Standard Mode —In standard mode, the NI 1409 receives an
incoming composite video signal from the external BNC or 68-pin
VHDCI connector and generates CSYNC, HSYNC, VSYNC, and
PCLK signals. The VHDCI connector outputs the generated CSYNC
signal to synchronize other image acquisition devices or cameras.
• CSYNC External Mode —In CYSNC external mode, the NI 1409
receives an incoming video signal (composite or luminance) and an
external CSYNC signal from the external connector and generates
HSYNC, VSYNC, and PCLK signals.
• External Lock Mode —In external lock mode, the NI 1409 receives
HSYNC, VSYNC, and PCLK signals from the camera and uses these