National Instruments 800 Series 사용자 설명서

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Chapter 1
Introduction
© National Instruments Corporation
1-5
VXIpc 800 Series User Manual
Custom Application-Specific Interface Chips
The VXIpc 800 Series uses the MITE and MANTIS custom ASICs to 
deliver high VXI performance, and can achieve more than 20 MB/s 
DMA block-mode data transfer rates across the VXI backplane.
The VXIpc 800 Series has the TNT4882C custom ASIC to give full 
GPIB control of external instruments via a front-panel connector. GPIB 
capability is fully compatible with IEEE 488.2 and the 
industry-standard NI-488.2 driver for a variety of operating systems.
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 800 is based on the MANTIS 
custom ASIC. The VXIpc 800 front panel has two SMB trigger I/O 
connectors, which you can use to route any of the TTL trigger lines 
between the backplane and external devices. The MANTIS ASIC on the 
VXIpc 800 provides the complete VXI interface to the backplane 
connector in a single chip. The VXIpc 800 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.
Note:
The MANTIS ASIC contains the exact functionality of the TIC ASIC, 
which appeared on the VXIpc-486 Model 500 Series controllers. Any 
application that currently uses any of the TIC functionality, such as the 
crosspoint switch and counter/timers, can run on a controller containing 
the MANTIS ASIC without modification.