HD6413008VF25 Datasheet, PDF (119/688 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

4. Exception Handling
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 (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 4.6 shows an example of what
happens when the SP value is odd.
Rev.4.00 Aug. 20, 2007 Page 73 of 638
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