8.1.4.4Breakpoint Interrupt (Interrupt Type 03h)

An interrupt caused by the 1-byte version of the INT instruction (INT3).

8.1.4.5INTO Detected Overflow Exception (Interrupt Type 04h)

Generated by an INTO instruction if the OF bit is set in the Processor Status Flags (FLAGS) Register.

8.1.4.6Array BOUNDS Exception (Interrupt Type 05h)

Generated by a BOUND instruction if the array index is outside the array bounds. The array bounds are located in memory at a location indicated by one of the instruction operands. The other operand indicates the value of the index to be checked.

8.1.4.7Unused Opcode Exception (Interrupt Type 06h)

Generated if execution is attempted on undefined opcodes.

8.1.4.8ESC Opcode Exception (Interrupt Type 07h)

Generated if execution of ESC opcodes (D8h–DFh) is attempted. The microcontrollers do not check the escape opcode trap bit. The return address of this exception points to the ESC instruction that caused the exception. If a segment override prefix preceded the ESC instruction, the return address points to the segment override prefix.

Note: All numeric coprocessor opcodes cause a trap. The Am186ER and Am188ER microcontrollers do not support the numeric coprocessor interface.

Interrupt Control Unit

8-7

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AMD Am188TMER, Am186TMER Breakpoint Interrupt Interrupt Type 03h, Into Detected Overflow Exception Interrupt Type 04h