Notes On Stack Usage - Hitachi H8/3008 Hardware Manual

4.6

Notes on Stack Usage

When accessing word data or longword data, the H8/3008 regards the lowest address bit as 0. The
stack should always be accessed by word access or longword access, and the value of the stack
pointer (SP:ER7) should always be kept even.
Use the following instructions to save registers:
PUSH.W Rn
PUSH.L ERn
Use the following instructions to restore registers:
POP.W Rn
POP.L ERn
Setting SP to an odd value may lead to a malfunction. Figure 4.6 shows an example of what
happens when the SP value is odd.
(or MOV.W Rn, @–SP)
(or MOV.L ERn, @–SP)
(or MOV.W @SP+, Rn)
(or MOV.L @SP+, ERn)
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