Troubleshooting
Appendix B
VME-AT2000/NI-VXI MS-DOS Getting Started
B-4
© National Instruments Corporation
Problems with RESMAN
If the
VXIINIT
program runs successfully but you encounter problems with
RESMAN
, the
Resource Manager program, the cause is probably the Master Window. The Master Window is a
64 KB block of contiguous memory in the PC AT upper memory space that the AT-MXI uses to
access the VXI/VME bus. The upper memory space of a PC AT is the region from 640 KB
(A000h) to 1024 KB (FFFFh). Several system resources, such as system ROM and video
memory, reside in this area. By default, the Master Window occupies a memory region from a
base address of D000h to DFFFh. You can change the Master Window base address by running
the VXI resource editor program, either
VXIEDIT
or
VXITEDIT
, and using the Logical
Address Configuration Editor to make the change.
A conflict in the Master Window of the AT-MXI can cause
RESMAN
to behave erratically. The
following are likely symptoms of a conflict in the Master Window configuration.
•
The
RESMAN
display shows multiple devices at Logical Address 0. (The AT-MXI should be
the only device at Logical Address 0.)
•
RESMAN
detects nonexistent devices.
•
The computer hangs when you run
RESMAN
.
The following paragraphs discuss the two main causes of a Master Window Base Address
conflict.
Memory Area Used by Another Device
Your system may contain a device that already occupies all or some of the upper memory area
that is allocated for the Master Window.
To solve this problem, first determine what area of upper memory your devices use. Then move
either your device or the Master Window Base Address to an unused area of upper memory.
If you have a Super VGA monitor, your system is likely to use video RAM. Generally, any
video RAM used by your PC AT occupies all or some of the upper memory from A000h to
BFFFh. If you have Ethernet networking cards, be aware that many of them occupy upper
memory. Many Ethernet cards have an upper memory base address of D000h or E000h.
Memory Area Used by Expanded-Memory Manager or Emulator
Your system may contain an expanded-memory manager or an expanded-memory emulator that
uses a block of upper memory within the range that is allocated for the Master Window.
To solve this problem, verify which expanded-memory manager or emulator you are using, and
prevent it from using upper memory within the Master Window address range. The following
examples show how to prevent various expanded-memory managers or emulators from using
upper memory within the default Master Window address range of D000h to DFFFh.
