Exception Processing - Fujitsu FR Family Instruction Manual

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").
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