Intel 80287 User Manual

PROTECTION
Table 7-4. Inter-Level Return Checks
Type of Check Exception·
Error Code
SP is not within Segment Limit
SF
0
SP + N + 7 is not in Segment Limit·
SF
0
RPL of Return CS is Greater than CPL
GP Return CS id
Return
CS Selector is not null
GP Return CS id
Return
CS segment is within Descriptor Table Limit
GP Return CS id
Return
CS Descriptor is a Code Segment
GP Return CS id
Return
CS Segment is Present
NP Return CS id
DPL
of Return Non-Conforming Code Segment RPL of CS GP
Return CS id
55 Selector at SP + N + 6 is not Null SF Return 55 id
55 Selector at SP + N + 6 is within Descriptor Table Limit SF Return 55 id
55 Descriptor is Writable Data Segment
SF Return 55 id
55 Segment is Present
SF Return 55 id
55 Segment DPL = RPL of CS
SF Return 55 id
'SF = Stack Fault, GP = General Protection Exception, NP = Not-Present Exception
7-22
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Intel 80287 Specifications

General

Brand	Intel
Model	80287
Category	Computer Hardware
Language	English