National Instruments NI-VXI - Manual (Page 26)

Chapter 2 Introduction to the NI-VXI Functions
© National Instruments Corporation 2-7 NI-VXI User Manual
bu s
NA TIO NAL IN STRUMENT S ®
bu s
NA TION AL IN STR UM EN TS ®
bus
N AT ION AL IN STR UMENT S ®
NA TION AL IN STR UM ENT S ®
bu s
Remote Controller
and Extender
Remote Controller
and Extender
External
Controller
Extender
Only
Figure 2-2 . An External Controller Connected Using MXI-2 to a
Number of Remote Controllers
The extender and controller Parameters
In NI-VXI, some functions require a parameter named extender or
controller. Since some extenders act as controllers, there is often
confusion concerning what logical addresses should be passed to these
functions.
The extender parameter is the logical address of a mainframe extender
on which the function should be performed. Usually, functions with an
extender parameter involve the mapping of interrupt lines or trigger
lines into or out of a frame.
The controller parameter is the logical address of an embedded,
external, extending, or remote controller. Usually, functions with a
controller parameter involve sourcing or sensing particular interrupts
or triggers in a frame. According to the definitions of the different
types of controllers, the only valid logical addresses for the controller
parameter are:
• The external or embedded controller on which the program is
running
• A parent-side VXI-MXI-2 or VME-MXI-2 in a frame