Datasheet

Section 4 Address Break
Rev.4.00 Nov. 02, 2005 Page 61 of 304
REJ09B0143-0400
4.3 Usage Notes
When an address break is set to an instruction after a conditional branch instruction, and the
instruction set when the condition of the branch instruction is not satisfied is executed (see figure
4.3), note that an address break interrupt request is not generated. Therefore an address break must
not be set to the instruction after a conditional branch instruction.
0134
Address bus
Address break
interrupt request
0136 102A 0138
[Register setting]
BNE
instruction
prefetch
NOP
instruction
prefetch
MOV
instruction
prefetch
NOP
instruction
prefetch
ABRKCR=H'80
BAR=H'0136
012A MOV.B . . .
: :
0134 BNE
*0136 NOP
0138 NOP
: :
[Program]
Figure 4.3 Operation when Condition is not Satisfied in Branch Instruction
When another interrupt request is accepted before an instruction to which an address break is set is
executed, exception handling of an address break interrupt is not executed. However, the ABIF bit
is set to 1 (see figure 4.4). Therefore the ABIF bit must be read during exception handling of an
address break interrupt.