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3.1
Program Execution State
In program execution state the CPU executes program instructions in sequence.
3.2
Exception Handling States
Exception-handling states are transient states occurring when exception handling is raised by a
reset or interrupt, and the CPU changes its normal processing flow, branching to a start address
acquired from a vector table. In exception handling caused by an interrupt, PC and CCR values
are saved to the stack, with reference made to a stack pointer (R7).
3.2.1
Types and Priorities of Exception Handling
Exception handling includes processing of reset exceptions and of interrupts. Table 3-1
summarizes the factors causing each kind of exception, and their priorities. Reset exception
handling has the highest priority.
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