Chapter 6 NI-VXI Configuration Utility
PCI-MXI-2 for Linux 6-24 ni.com
Caution Do not install a VXI/VME-MXI-2 configured for VMEbus System Controller
(VXI Slot 0) into another slot without first reconfiguring it to either Non-Slot 0 or
automatic configuration. Neglecting to do this could damage the VXI/VME-MXI-2,
theVXI/VMEbus backplane, or both.
This means that you should use either the No option or the Auto option of this control.
Forthe VXI-MXI-2, you also have the option of changing the hardware jumper setting.
VXI/VME Bus Timeout Value
The VXI/VMEbus Bus Timeout (BTO) is a watchdog timer for transfers on
the VMEbus Data Transfer bus. After the specified amount of time has
elapsed, the BTO circuitry terminates a VMEbus cycle if no slave has
responded. The VXI/VME-MXI-2 must provide the VXI/VMEbus BTO
for proper operation because when a MXIbus cycle is involved, the
VXI/VMEbus timeout must be disabled and the MXIbus BTO enabled.
You should disable the BTO of any other BTO module residing in the
mainframe. If this is not possible, set its VXI Bus Timeout control to its
maximum setting to give the MXIbus cycles as much time as possible to
complete.
The lowest value in the allowable range is 15 µs and the highest value is
256 ms. The default value is 125 µs.
Advanced VXI Settings
Click the Advanced button to reach additional configuration options
forthe VXI/VME Bus portion of this editor, as shown in Figure 6-9.
Theseoptions are intended for more advanced users.