Intel iapx 432 manual System OBJEClS Structurfs

SYSTEM OBJECl'S STRUCTURFS

The base displacement field contains the byte displacement into the 432 segment used to construct a refinement of a data segment. See Figure 3-2 for an illustration of the role of a window's base displacement in forming a refinement.

Mapping Facility Fault Information Area -

The mapping facili ty fault information area consists of an entry fault code and fault displacement pair for each map entry. Diagranmatically, the fault information for each map entry appears as shown beiCM.

=		=
1	----------------	1
1	fault disp	1
1	----------------	1
1	fault code	!
1	----------------	1
=		=

Each entry fault code field is used to record the cause of the last

fault associated with that map entry. It has the following organization.

Ix! 6 bits lxlxlxlxlxlxlxlxlxl

1	1
1 1 1--		read/write
1 1	----	bus error
1 1------		access rights
1 1-------		segment bound
1 1----------		memory overflCM
1------------		access direction
1--------------		post termination
1---------------		partial block overflCM
1------------------		block overflow
1------------------------		reserved
1-----------------------------		block termination
		(internal use)

The I-bit read/write subfield indicates whether the associated fault was caused by a read request or a wr i te request. A value of zero irrlicates that the fault was caused by a read request. A value of one indicates that the fault was caused by a write request.

The I-bit bus error subfield indicates whether or not the associated faul t was caused by a 432 bus error. A value of zero indicates that the fault was not caused by a bus error. A value of one indicates that the fault was caused by a bus error.

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