Renesas SH7781 - Manual (Page 1509)

29. User Break Controller (UBC)
Rev.1.00 Jan. 10, 2008 Page 1479 of 1658
REJ09B0261-0100
29.3.6 Program Counter Value to be Saved
When a break has occurred, the address of the instruction to be executed when the program
restarts is saved in the SPC then the exception handling state is initiated. A unique instruction
causing a break can be identified unless the data value is included in the match conditions.
1. When the instruction fetch cycle (before instruction execution) is specified as the match
condition:
The address of the instruction which has satisfied the match conditions is saved in the SPC.
The instruction which has satisfied the match conditions is not executed, but a break occurs
instead. However, if the match conditions are satisfied for the delayed slot instruction, the
address of the delayed branch instruction is saved in the SPC.
2. When the instruction fetch cycle (after instruction execution) is specified as the match
condition:
The address of the instruction immediately after the instruction which has satisfied the match
conditions is saved in the SPC. The instruction which has satisfied the match conditions is
executed, then a break occurs before the next instruction. If the match conditions are satisfied
for the delayed branch instruction or its delayed slot, these instructions are executed and the
address of the branch destination is saved in the SPC.
3. When the operand access (address only) is specified as the match condition:
The address of the instruction immediately after the instruction which has satisfied the break
conditions is saved in the SPC. The instruction which has satisfied the match conditions are
executed, then a break occurs before the next instruction. However, if the conditions are
satisfied for the delayed slot, the address of the branch destination is saved in the SPC.
4. When the operand access (address and data) is specified as the match condition:
If the data value is added to the match conditions, the instruction which has satisfied the match
conditions is executed. A user break occurs before executing an instruction that is one through
six instructions after the instruction which has satisfied the match conditions. The address of
the instruction is saved in the SPC; thus, it is impossible to identify exactly where a break will
occur. If the conditions are satisfied for the delayed slot instruction, the address of the branch
destination is saved in the SPC. If a branch instruction follows the instruction which has
satisfied the match conditions, a break may occur after the delayed instruction and delayed slot
are executed. In this case, the address of the branch destination is also saved in the SPC.