Chapter 6
NI-VXI Configuration Utility
©
National Instruments Corporation
6-17
MXI Bus System Controller
You can use the System Controller option to determine whether the
VXI/VME-MXI-2 acts as the MXI Bus System Controller. When the Auto
setting (the default setting) is active, the VXI/VME-MXI-2 automatically
can sense from the MXIbus cable whether it should be the controller.
You can select either Yes or No to manually determine if the
VXI/VME-MXI-2 should be the MXI Bus System Controller. You must
still be certain to cable the MXIbus system appropriately when you make
either of these selections.
MXI Bus Timeout Value
The MXI Bus Timeout (BTO) is a watchdog timer for transfers on
the MXIbus. The MXIbus BTO unit operates only when the
VXI/VME-MXI-2 is acting as the MXI Bus System Controller. The
functionality of this option is similar to that of the VXI Bus Timeout
option described previously under the
section.
The options range from 8
µ
s to 128 ms, with a default value of 1 ms.
After the specified amount of time has elapsed, the BTO circuitry
terminates a MXIbus cycle if no slave has responded. The BTO circuitry is
automatically deactivated when the VXI/VME-MXI-2 is not acting as the
MXI Bus System Controller. The BTO is also disabled when the current
MXIbus cycle maps to the VXI/VMEbus through a VXI/VME-MXI-2.
Advanced MXI Settings
Select the Advanced option to reach additional configuration options for
the MXI Bus portion of this editor. These options are intended for more
advanced users.
MXI Auto Retry
The VXI/VME-MXI-2 has an automatic retry feature for cycles that map
from the MXIbus to the VXI/VMEbus. This feature works in the same
manner as the Auto Retry option described previously under the
section. By default, this option is disabled.