MultiProcessor Specification
Table 4-16. Compatibility Bus Address Space Modifier Entry Fields
| Offset | Length |
|
Field | (in | (in bits) | Description |
| bytes:bits) |
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ENTRY TYPE | 0 | 8 | Entry type 130 identifies a Compatibility Bus |
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| Address Space Modifier Entry. |
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ENTRY LENGTH | 1 | 8 | A value of 8 indicates that an entry of this type is |
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| eight bytes long. |
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BUS ID | 2 | 8 | Bus for address space mappings are to be |
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| modified. This number corresponds to the BUS |
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| ID as defined in the base table entry for this bus. |
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ADDRESS MODIFIER:PR | 3:0 | 1 | If this bit is set to one, the address ranges |
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| specified by PREDEFINED RANGE LIST are to |
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| be subtracted from the address space |
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| associated with the bus. If this bit is set to zero, |
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| the specified address ranges are to be added to |
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| the address space associated with the bus. |
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PREDEFINED RANGE LIST | 4 | 32 | A number that indicates the list of predefined |
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| address space ranges that this record will |
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| modify for the bus. |
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PREDEFINED RANGE LIST may take one of the values from Table
Table 4-17. Predefined Range Lists
List | Value | Address Ranges |
ISA Compatible I/O Range | 0 | |
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| |
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| |
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| |
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VGA Compatible I/O Range | 1 | X3B0 - X3BB |
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| X3C0 - X3DF |
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| X7B0 - X7BB |
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| X7C0 - X7DF |
|
| XBB0 - XBBB |
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| XBC0 - XBDF |
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| XFB0 - XFBB |
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| XFC0 - XFDF |
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|
All addresses in Table
Version 1.4 |