Chapter 3 Hardware Overview
IMAQ PCI-1428 User Manual 3-4 ni.com
Multiple-Tap Data Formatter
Many digital cameras transfer multiple taps, or channels, of data
simultaneously to increase the frame rate of the camera. However, the data
in each tap may not be transferred in the traditional top-left to bottom-right
direction. Also, the taps may not transfer data in the same direction.
The multiple-tap data formatting circuitry on the PCI-1428 can reorder the
data from up to four taps. The data from each tap can beindependently
scanned either from left-to-right or right-to-left and top-to-bottom or
bottom-to-top.
Note For your convenience, data reformatting instructions for these cameras have been
preprogrammed into the camera files.
SDRAM
The PCI-1428 has 16 MB of onboard high-speed synchronous dynamic
RAM (SDRAM). The PCI-1428 uses the onboard RAM as a FIFO buffer
to ensure acquisition. Even when the data rate from the camera exceeds PCI
throughput, you can acquire without interruption until the onboard RAM is
full.
Trigger Control and Mapping Circuitry
The trigger control and mapping circuitry routes, monitors, and drives
theexternal and RTSI bus trigger lines. You can configure each line to start
an acquisition on a rising or falling edge and drive each line asserted or
unasserted, much like a digital I/O line. You canalso map pulses from the
high-speed timing circuitry or many of the PCI-1428 status signals to these
trigger lines. Four external and four RTSI bus triggers (all of which are
programmable for polarity and direction) are available for simultaneous
use.
High-Speed Timing
Built from high-speed counters, the high-speed timing circuitry on the
PCI-1428 can generate precise real-time control signals for your camera.
Map the output of this circuitry to a trigger line to provide accurate pulses
and pulse trains. Use these control signals to control exposure time and
frame rate.
Note For your convenience, the external control for cameras that support it has been
preprogrammed into the camera file. You can use MAX to specify the frequency and