Fault Types - Intel i960 Jx Developer's Manual

8.2

FAULT TYPES

The i960 architecture defines a basic set of faults that are categorized by type and subtype. Each
fault has a unique type and subtype number. When the processor detects a fault, it records the fault
type and subtype numbers in the fault record. It then uses the type number to select the fault
handling procedure.
The fault handling procedure can optionally use the subtype number to select a specific fault handling
action. The i960 Jx processor recognizes i960 architecture-defined faults and a new fault subtype for
detecting unaligned memory accesses.
arranged by type and subtype. Text that follows the table gives column definitions.
Table 8-1. i960
Fault Type
Number Name
0H OVERRIDE
0H PARALLEL
1H TRACE
2H OPERATION
3H ARITHMETIC
4H Reserved
5H CONSTRAINT
6H Reserved
7H PROTECTION
8H - 9H Reserved
AH TYPE
BH - FH Reserved
Table 8-1 lists all faults that the i960 Jx processor detects,
®
Jx Processor Fault Types and Subtypes
Fault Subtype
Number or
Name
Bit Position
NA NA
NA NA
Bit 1 INSTRUCTION
BRANCH
Bit 2
Bit 3 CALL
Bit 4 RETURN
Bit 5 PRERETURN
Bit 6 SUPERVISOR
Bit 7 MARK/BREAKPOINT
1H INVALID_OPCODE
2H UNIMPLEMENTED
3H UNALIGNED
4H INVALID_OPERAND
1H INTEGER_OVERFLOW
2H ZERO-DIVIDE
1H RANGE
Bit 1 LENGTH
1H MISMATCH
FAULTS
Fault Record
See section 8.10.4,
"OVERRIDE Faults"
(pg. 8-26)
see section 8.6.4,
"Parallel Faults" (pg. 8-9)
0001 0002H
0001 0004H
0001 0008H
0001 0010H
0001 0020H
0001 0040H
0001 0080H
0002 0001H
0002 0002H
0002 0003H
0002 0004H
0003 0001H
0003 0002H
0005 0001H
0007 0002H
000A 0001H
8-3
8