Chapter 1
Introduction
VXIpc-850 Series User Manual
1 - 4
© National Instruments Corporation
The CPU module and its memory sockets are easily accessible for you
to install additional DRAM in the field—up to 128 MB. The
VXIpc-850 contains at least an 800 MB internal, enhanced IDE hard
disk. For information on adding RAM by installing SIMMs, refer to
Appendix A, Specifications .
Slot 0 Functionality
You can use the VXIpc -850 Series computers to achieve full VXI
Slot 0 control of your VXI system. You can also install the VXIpc-850
in another slot and use it in Non-Slot 0 mode. You do not have to
change any switches or jumpers when moving between these two
modes, as the VXIpc -850 can automatically detect whether it is
installed in Slot 0 and it will automatically enable or disable the Slot 0
onboard circuitry.
Custom Application-Specific Interface Chips
The VXIpc-850 Series uses the MITE, MANTIS, and TNT4882C
custom ASICs to deliver high VXI and GPIB performance, and can
achieve more than 20 MB/s DMA block-mode data transfer rates across
the VXI backplane.
The MITE custom ASIC is a sophisticated dual-channel DMA
controller with standard interfaces for VXI and PCI. By using MITE
DMA to transfer data and commands to and from devices, the MITE
frees the computer’s microprocessor to perform other tasks such as data
analysis and presentation. In addition to DMA, the MITE incorporates
the new VME64 MBLT (8-byte block transfers in which both the
address bus and data bus are used to transfer data) directly into the
ASIC to perform the fastest transfer operation to instruments. With the
multiple windowing scheme of the MITE, you can easily access all of
VXI address space.
The VXI trigger interface on the VXIpc-850 is based on the MANTIS
custom ASIC. By using the two SMB trigger I/O connectors on the
front panel, you can route any of the TTL trigger lines between the
backplane and external devices. The MANTIS provides the complete
VXI interface to the backplane connector in a single chip. The
VXIpc-850 can respond to all VXI-defined protocols on all P2 TTL and
ECL trigger lines at the same time. The MANTIS features an internal
cross-matrix switching system for routing between lines as well as to
and from the front panel and onboard clocks.
The VXIpc-850 uses the TNT4882C custom ASIC to give full GPIB
control of external instruments via a front-panel connector. GPIB
