HD6432160 RENESAS [Renesas Technology Corp], HD6432160 Datasheet - Page 124

• Manufacturer Part Number: HD6432160
• Description: Hitachi 16-Bit Single-Chip Microcomputer
• Manufacturer: RENESAS [Renesas Technology Corp]

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. 2.0, 08/02, page 84 of 788
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'FFFEFF
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
TRAPA instruction executed
Figure 4.3 Operation when SP Value is Odd
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