Renesas H8S/2111B 用户手册

Rev. 1.00, 05/04, page 65 of 544 

 

When accessing word data or longword data, this LSI assumes that the lowest address bit is 0. The 
stack should always be accessed in words or longwords, and the value of the stack pointer (SP: 
ER7) should always be kept even. 

Use the following instructions to save registers: 

PUSH.W   Rn    (or MOV.W Rn, @-SP) 

PUSH.L   ERn   (or MOV.L ERn, @-SP) 

 

Use the following instructions to restore registers: 

POP.W    Rn    (or MOV.W @SP+, Rn)  

POP.L    ERn   

(or

 MOV.L @SP+, ERn

)

 

 

Setting SP to an odd value may lead to a malfunction. Figure 4.3 shows an example of what 
happens when the SP value is odd. 

SP

CCR:

PC:

R1L:

SP:

Condition code register

Program counter

General register R1L

Stack pointer

CCR

SP

SP

R1L

H'FFEFFA

H'FFEFFB

H'FFEFFC

H'FFEFFD

H'FFEFFF

PC

PC

TRAPA instruction executed

SP set to H'FFFEFF

Data saved above SP

MOV.B R1L, @-ER7 executed

Contents of CCR lost

Address

[Legend]

Note: This diagram illustrates an example in which the interrupt control mode is 0 in advanced mode.