H8S2110B RENESAS [Renesas Technology Corp], H8S2110B Datasheet - Page 100

• Manufacturer Part Number: H8S2110B
• Description: Renesas 16-Bit Single-Chip Microcomputer Renesas H8S Family/H8S/2100 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

Section 4 Exception Handling
4.7
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:
Use the following instructions to restore registers:
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.
Rev. 2.00 Mar 21, 2006 page 62 of 518
REJ09B0299-0200
PUSH.W
PUSH.L
POP.W
POP.L
SP
Usage Note
Note: This diagram illustrates an example in which the interrupt control mode is 0 in advanced mode.
Legend:
CCR :
R1L :
PC :
SP :
SP set to H'FFEFFF
Rn
ERn
Rn
ERn
Condition code register
Program counter
General register R1L
Stack pointer
(or MOV.W Rn, @-SP)
(or MOV.L ERn, @-SP)
(or MOV.W @SP+, Rn)
(or
Figure 4.3 Operation When SP Value Is Odd
TRAPA instruction executed
MOV.L @SP+, ERn
SP
Data saved above SP
CCR
PC
)
MOV.B R1L, @-ER7 executed
SP
Contents of CCR lost
R1L
PC
H'FFEFFA
H'FFEFFB
H'FFEFFC
H'FFEFFD
H'FFEFFF
Address