User manual

Chapter 3 VXI-MXI-2 Configuration and Installation

Removing the Metal Enclosure

The VXI-MXI-2 is housed in a metal enclosure to improve EMC

performance and to provide easy handling. Because the enclosure

includes cutouts to facilitate changes to the switch and jumper settings,

it should not be necessary to remove it under normal circumstances.

However, it is necessary to remove the enclosure if you want to change

the amount of DRAM installed on the VXI-MXI-2. Switch S6, which is

directly related to the amount of DRAM you want to install, is also

accessible only by removing the enclosure. If you will be making this

change, remove the four screws on the top, the four screws on the

bottom, and the five screws on the right side cover of the enclosure.

Refer to the Onboard DRAM section later in this chapter for details

about changing DRAM.

VXIbus Logical Address

Each device in a VXIbus/MXIbus system is assigned a unique number

between 0 and 254. This 8-bit number, called the logical address,

defines the base address for the VXI configuration registers located on

the device. With unique logical addresses, each VXIbus device in the

system is assigned 64 bytes of configuration space in the upper 16 KB

of A16 space.

Logical address 0 is reserved for the Resource Manager in the VXIbus

system. Because the VXI-MXI-2 cannot act as a Resource Manager, do

not configure the VXI-MXI-2 with a logical address of 0.

Some VXIbus devices have dynamically configurable logical

addresses. These devices have an initial logical address of hex FF or

255, which indicates that they can be dynamically configured. While

the VXI-MXI-2 does support dynamic configuration of VXI devices

within its mainframe, it is itself a statically configured device and is

preset at the factory with a VXI logical address of 1.

Ensure that no other statically configurable VXIbus devices have a

logical address of 1. If they do, change the logical address setting of

either the VXI-MXI-2 or the other device so that every device in the

system has a unique associated logical address.