Renesas SH7781 用户手册

29.   User Break Controller (UBC) 

Rev.1.00  Jan. 10, 2008  Page 1473 of 1658 

REJ09B0261-0100 

 

"Instruction fetch" refers to an access in which an instruction is fetched. For example, fetching the 
instruction located at the branch destination after executing a branch instruction is an instruction 
access. "Operand access" refers to any memory access accompanying execution of an instruction. 
For example, accessing an address (PC 

+ disp × 2 + 4) in the instruction MOV.W@(disp,PC),Rn 

is an operand access. "Data" is used in contrast to "address".  

All types of operand access are classified into read or write access. Special care must be taken in 
using the following instructions.  

•  PREF, OCBP, and OCBWB: Instructions for a read access 
•  MOVCA.L and OCBI: Instructions for a write access 
•  TAS.B: Instruction for a single read access or a single write access 

 

The operand access accompanying the PREF, OCBP, OCBWB, and OCBI instructions is access 
without the data value; therefore, do not include the data value in the match conditions for these 
instructions.  

The operand size should be defined for all types of operand access. Available operand sizes are 
byte, word, longword, and quadword. For operand access accompanying the PREF, OCBP, 
OCBWB, MOVCA.L, and OCBI instructions, the operand size is defined as longword.