SH7065 Datasheet, PDF (195/941 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7000 Series

Section 5 Exception Handling
5.6 Cases in Which Exceptions Are Not Accepted
There are cases, as shown in table 5.9, in which, if an address error or interrupt occurs after a
delayed branch instruction or an interrupt for which interruption is prohibited, the exception is not
accepted immediately, but is held pending. In such cases, the address error or interrupt will be
accepted when an instruction for which exception acceptance is permitted is decoded.
Table 5.9 Exception Occurrence: Special Cases
Exception Source
Point of Occurrence
Immediately after a delayed branch instruction^*1
Address Error Interrupt
Not accepted Not accepted
Immediately after an instruction for which interruption is
prohibited^*2
Accepted
Not accepted
Repeat loop comprising up to three instructions
(instruction fetch cycle not generated)
Not accepted Not accepted
First instruction or last three instructions in a repeat loop
containing four or more instructions
Fourth from last instruction in a repeat loop containing
four or more instructions
Accepted
Not accepted
Notes: 1. Delayed branch instructions: JMP, JSR, BRA, BSR, RTS, RTE, BF/S, BT/S, BSRF,
BRAF
2. Instructions for which interruption is prohibited: LDC, LDC.L, STC, STC.L, LDS, LDS.L,
STS, STS.L
5.6.1 After a Delayed Branch Instruction
When an instruction located immediately after a delayed branch instruction (i.e. in the delay slot)
is decoded, neither an address error nor an interrupt is accepted. As a delayed branch instruction
and the instruction located immediately after it (in the delay slot) are always executed
consecutively, exception handling is not initiated during this period.
5.6.2 After an Instruction for Which Interruption Is Prohibited
When the instruction immediately following an instruction for which interruption is prohibited is
decoded, an interrupt is not accepted. However, an address error exception is accepted.
Rev. 5.00 Sep 11, 2006 page 173 of 916
REJ09B0332-0500