Xembedded XVME-689-VR7, User Manual

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BIOS Setup Menus
3-27
Table 3-1 Slave Interface Submenu
Option Description
Slave Interface
Used to turn the slave interface boot state On or Off (default). When turned Off, other
VME masters cannot access memory on the XVME 689-VR7.
Address Modifiers Determines which type of VMEbus slave access is permitted to read or write to the
XVME 689-VR7 dual-access memory. The first field determines whether the slave
interface responds to Data access only (default), Program access only, or Both. The
second field determines whether the slave interface responds to Supervisory access
only, Non-Privileged access only (default), or Both.
Address Space Determines if VME masters access the slave's dual-access memory in the VMEbus
Standard (A24) or VMEbus Extended (A32) address space. The default is VMEbus
Extended.
Size Determines the amount of dual-access memory that is available to external VMEbus
masters. The slave memory size cannot be more than the total memory size, or
greater than 16 MB for VMEbus Standard Address Space. The choices are 1MB
(default), 2MB, 4MB, 8MB, 16MB, and 32MB (unavailable for VMEbus Standard
Address Space).
Base Address High Nibble
Base Address Med. Nibble
Base Address Low Nibble These fields determine the base VMEbus address prefix for the first 12 bits of the
address to which the VMEbus slave interface will respond. The three fields are the
high (H), middle (M), and low (L) nibbles of these 12 bits. The address is HML00000h.
In the default screen configuration H is A, M is A, and L is 4, so the address is
AA400000h.
The values change depending on the Size and Address Space field values. When the
Address Space value is VMEbus Standard, the dual-access memory must be located
on a 1 MB boundary and the upper two nibbles are ignored, so the high and medium
nibbles are changed to 0 and are made read-only. When the Address Space value is
VMEbus Extended, the slave address must be a multiple of the slave memory size.
When the Size is greater than 1 MB, the low nibble is truncated to an even value.
Note: The address that is set with these fields is the address that is used by the
VMEbus processors. The PC/AT processor on the XVME 689-VR7 will see a
translated address. This translation (and the amount of translation) is calculated by the
BIOS and is not user-configurable in the BIOS setup. See p. 4-5 for a discussion of
translation addresses.