Chapter 2
Hardware Configuration and Installation
© National Instruments Corporation
2-15
VME-AT2000/NI-VXI MS-DOS Getting Started
Front Panel Features
The VME-MXI has the following front panel features:
•
Three front panel LEDs
–
FAILED LED indicates that the VMEbus SYSFAIL line is asserted.
–
VME ACCESS LED indicates when the VME-MXI is accessed from the VMEbus.
–
MXI ACCESS LED indicates when the VME-MXI is accessed from the MXIbus.
•
MXIbus connector
•
System reset pushbutton
•
INTX connector (if your VME-MXI includes the INTX daughter card option)
VMEbus System Controller
The VME-MXI is shipped from the factory configured to be installed in Slot 1 of the VMEbus
chassis as the VMEbus System Controller. If another device is already in Slot 1, you must
decide which device will be the VMEbus System Controller and reconfigure the other device as
non-VMEbus System Controller.
When the VME-MXI is the VMEbus System Controller, it has the VMEbus Data Transfer Bus
Arbiter capability (PRI ARBITER) and it drives the 16-MHz VMEbus system clock. The
VMEbus Data Transfer Bus Arbiter circuitry accepts bus requests on all four VMEbus request
levels, prioritizes the requests, and grants the bus to the highest priority requester. The VMEbus
system clock is driven by an onboard 16-MHz oscillator with a 50%
±
5% duty cycle.
If you want to install the VME-MXI into a VXIbus mainframe, you can install it in any slot
except Slot 0. The VME-MXI has VXIbus configuration registers, which makes it compatible
with the VXIbus specification. However, the VME-MXI does not have the CLK10 and MODID
circuitry required by a Slot 0 VXIbus device. Therefore, configure the VME-MXI as a non-
VMEbus System Controller and install it in any other slot.
Figure 2-8(a) shows the default configuration setting for the VME-MXI installed as the VMEbus
System Controller. To configure the VME-MXI as a non-VMEbus System Controller, change
slide switch S5 as depicted in Figure 2-8(b).
S5
S5
a. VMEbus System
Controller (Default Setting)
b. Not VMEbus
System Controller
Figure 2-8. VMEbus System Controller Selection