National Instruments NI 6238 - Manual (Page 128)

Chapter 11 Bus Interface
NI 6238/6239 User Manual 11-2 ni.com
Each DMA controller supports packing and unpacking of data through the
FIFOs to connect different size devices and optimize PCI bus utilization
and automatically handles unaligned memory buffers.
PXI Considerations
Note PXI clock and trigger signals are only available on PXI devices. Other devices use
RTSI.
PXI Clock and Trigger Signals
Refer to the PXI_CLK10 , PXI Triggers , PXI_STAR Trigger , and
PXI_STAR Filters sections of Chapter 10, Digital Routing and Clock
Generation , for more information on PXI clock and trigger signals.
PXI and PXI Express
NI PXI-6238/6239 modules can be installed in any PXI chassis and most
slots of PXI Express chassis.
PXI specifications are developed by the PXI System Alliance
(
www.pxisa.org ). Using the terminology of the PXI specifications,
NI PXI-6238/6239 devices are 3U Hybrid Slot-Compatible PXI-1
Peripheral Modules.
3U designates devices that are 100 mm tall (as opposed to the taller 6U
modules).
Hybrid slot-compatible defines where the device can be installed.
PXI-6238/6239 devices can be installed in the following chassis and slots:
• PXI chassis—PXI-6238/6239 devices can be installed in any
peripheral slot of a PXI chassis.
• PXI Express chassis—PXI-6238/6239 devices can be installed in the
following PXI Express chassis slots:
– PXI-1 slots—Accepts all PXI modules
– PXI hybrid slots—Accepts PXI or PXI Express modules.
PXI-1 devices use PCI signaling to communicate to the host controller (as
opposed to PCI Express signaling).
Peripheral devices are installed in peripheral slots and are not system
controllers.