National Instruments VXI-USB User Manual
Glossary
© National Instruments Corporation
G-9
VME
Versa Module Eurocard or IEEE 1014
VMEbus System
Controller
Controller
A device configured for installation in Slot 0 or a VXIbus mainframe or the
first slot in a VMEbus chassis. This device is unique in the VMEbus system
in that it performs the VMEbus System Controller functions, including
clock sourcing and arbitration for data transfers across the backplane.
Installing such a device into any other slot can damage the device, the
VMEbus/VXIbus backplane, or both.
first slot in a VMEbus chassis. This device is unique in the VMEbus system
in that it performs the VMEbus System Controller functions, including
clock sourcing and arbitration for data transfers across the backplane.
Installing such a device into any other slot can damage the device, the
VMEbus/VXIbus backplane, or both.
VXIbus
VMEbus Extensions for Instrumentation
W
W
watts
Word Serial Protocol
The simplest required communication protocol supported by
message-based devices in a VXIbus system. It utilizes the A16
communication registers to transfer data using a simple polling handshake
method.
message-based devices in a VXIbus system. It utilizes the A16
communication registers to transfer data using a simple polling handshake
method.
write posting
A mechanism that signifies that a device will immediately give a successful
acknowledge to a write transfer and place the transfer in a local buffer. The
device can then independently complete the write cycle to the destination.
acknowledge to a write transfer and place the transfer in a local buffer. The
device can then independently complete the write cycle to the destination.