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Renesas SH7781 User Manual

Page 154

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5. Exception Handling

Rev.1.00 Jan. 10, 2008 Page 124 of 1658
REJ09B0261-0100

other exceptions is determined depending on the processing mode by SR after restoring or
the BL bit. The completion type exception is accepted before branching to the destination
of RTE instruction. However, if the re-execution type exception is occurred, the operation
cannot be guaranteed.

B. The user break is not accepted by the instruction in the delay slot of the RTE instruction.

(5)

Changing the SR Register Value and Accepting Exception

A. When the MD or BL bit in the SR register is changed by the LDC instruction, the

acceptance of the exception is determined by the changed SR value, starting from the next
instruction.* In the completion type exception, an exception is accepted after the next
instruction has been executed. However, an interrupt of completion type exception is
accepted before the next instruction is executed.

Note: * When the LDC instruction for SR is executed, following instructions are fetched again

and the instruction fetch exception is evaluated again by the changed SR.