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Rev. 1.00, 05/04, page 19 of 544
The memory indirect addressing mode (@@aa:8) employed in the JMP and JSR instructions
uses an 8-bit absolute address included in the instruction code to specify a memory operand
that contains a branch address. In advanced mode, the operand is a 32-bit longword operand,
providing a 32-bit branch address. The upper 8 bits of these 32 bits are a reserved area that is
regarded as H'00. Branch addresses can be stored in the area from H'00000000 to H'000000FF.
Note that the top area of this range is also used for the exception vector table.
• Stack structure
In advanced mode, when the program counter (PC) is pushed onto the stack in a subroutine
call, and the PC and condition-code register (CCR) are pushed onto the stack in exception
handling, they are stored as shown in figure 2.4. The extended control register (EXR) is not
pushed onto the stack. For details, see section 4, Exception Handling.
(a) Subroutine Branch (b) Exception Handling
PC
(24 bits)
CCR
PC
(24 bits)
SP
SP
Reserved
Figure 2.4 Stack Structure in Advanced Mode