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4 exception processing, Exception processing – FUJITSU FR family 32-bit microcontroller instruction manuel CM71-00101-5E User Manual

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CHAPTER 4 RESET AND "EIT" PROCESSING

4.4

Exception Processing

Exceptions originate from within the instruction sequence. Exceptions are processed
by first saving the necessary information to resume the currently executing instruction,
and then starting the processing routine corresponding to the type of exception that
has occurred.

Overview of Exception Processing

Exceptions originate from within the instruction sequence. Exceptions are processed by first saving the

necessary information to resume the currently executing instruction, and then starting the processing

routine corresponding to the type of exception that has occurred.

Branching to the exception processing routine takes place before execution of the instruction that has

caused the exception.

The address of the instruction in which the exception occurs becomes the program counter (PC) value that

is saved to the stack.

Factors Causing Exception Processing

The factor which causes the exception processing is the undefined-instruction exception (For details, see

"4.4.1 Undefined Instruction Exceptions").