Chapter
6 NI-VXI
Configuration
Utility
©
National Instruments Corporation
6-23
This means that you should use either the
No
option or the
Auto
option of this control.
For the 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
µ
s and the highest value is
256 ms. The default value is 125
µ
s.
Advanced VXI Settings
Click the
Advanced
button to reach additional configuration options
for the VXI/VME Bus portion of this editor, as shown in Figure 6-9.
These options are intended for more advanced users.
Figure 6-9.
Advanced VXI Settings