SH7713 Datasheet, PDF (323/904 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series

Section 9 User Break Controller
9.3.2 Break on Instruction Fetch Cycle
1. When L bus/instruction fetch/read/word or longword is set in the break bus cycle register
(BBRA or BBRB), the break condition becomes the L bus instruction fetch cycle. Whether it
breaks before or after the execution of the instruction can then be selected with the PCBA or
PCBB bit of the break control register (BRCR) for the appropriate channel. If an instruction
fetch cycle is set as a break condition, clear LSB in the break address register (BARA or
BARB) to 0. A break cannot be generated as long as this bit is set to 1.
2. An instruction set for a break before execution breaks when it is confirmed that the instruction
has been fetched and will be executed. This means this feature cannot be used on instructions
fetched by overrun (instructions fetched at a branch or during an interrupt transition, but not to
be executed). When this kind of break is set for the delay slot of a delayed branch instruction,
the break is generated prior to execution of the delayed branch instruction.
Note: If a branch does not occur at a delay condition branch instruction, the subsequent
instruction is not recognized as a delay slot.
3. When the condition is specified to be occurred after execution, the instruction set with the
break condition is executed and then the break is generated prior to the execution of the next
instruction. As with pre-execution breaks, this cannot be used with overrun fetch instructions.
When this kind of break is set for a delayed branch instruction and its delay slot, a break is not
generated until the first instruction at the branch destination.
4. When an instruction fetch cycle is set for channel B, the break data register B (BDRB) is
ignored. Therefore, break data cannot be set for the break of the instruction fetch cycle.
5. If the I bus is set for a break of an instruction fetch cycle, the condition is determined for the
instruction fetch cycles on the I bus. For details, see 5 in section 9.3.1, Flow of the User Break
Operation.
9.3.3 Break on Data Access Cycle
1. If the L bus is specified as a break condition for data access break, condition comparison is
performed for the logical addresses (and data) accessed by the executed instructions, and a
break occurs if the condition is satisfied. If the I bus is specified as a break condition, condition
comparison is performed for the physical addresses (and data) of the data access cycles that are
issued on the I bus by all bus masters including the CPU, and a break occurs if the condition is
satisfied. For details on the CPU bus cycles issued on the I bus, see 5 in section 9.3.1, Flow of
the User Break Operation.
2. The relationship between the data access cycle address and the comparison condition for each
operand size is listed in table 9.3.
Rev.1.50 Aug. 30, 2006 Page 283 of 860
REJ09B0288-0150