Board Number; Window Address Selection - Xycom XVME-976/202 Manual

The memory window size is 64 Kbytes. Devices containing 32 Kbytes appear
at the window address at offset 0 and are duplicated at offset 8000h. Pro-
grammers must be aware that BIOS extension programs triggered by 55AAh
may reinstall themselves since they might appear more than once in the mi-
croprocessor's address space. The optional Ampro XVME-956/101 Support
Software will not reinstall itself.

Board Number

The BD0 and BD1 bits in Control Register 1 select the desired module.
Each XVME-956/101 module is jumpered for a particular board number, 0
to 3, corresponding to the values of BD0 and BD1. Only one module per
control register I/O port address may be jumpered to a given board number.
At power up, the control registers of all XVME-956/101 modules are reset to
0.
Multiple XVME-956/101 modules with board number 1, 2, or 3, may be
used if they are jumpered for different control register I/O ports. You must
be sure the software disables the modules at one I/O address before enabling
a module at a different I/O address.
A module jumpered to board number 0 is different. A system may contain, at
most, one module with Board number 0.

Window Address Selection

The XVME-956/101 unit memory appears in a 64K window at either
D0000h or E0000h. The address of the window is jumper selected.
Chapter 4 - Memory Expansion Module Installation
Note
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