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CHAPTER 3 CPU ARCHITECTURE
User’s Manual U12697EJ3V0UM
Cautions 1. In stack addressing, the entire 1 MB space can be accessed, but the stack cannot be
guaranteed in the SFR area and internal ROM area.
2. The stack pointer (SP) becomes undefined when RESET is input. In addition, even when SP
is in the undefined state, non-maskable interrupts can be acknowledged. Therefore, when
the SP is in the undefined state immediately after the reset is cleared and a request for a non-
maskable interrupt is generated, unexpected operations sometimes occur. To avoid this
danger, always specify the following in the program after clearing a reset.
RSTVCT
CSEG AT 0
DW
RSTSTRT
INITSEG
CSEG BASE
RSTSTRT:
LOCATION 0H; or LOCATION 0FH
MOVG SP, #STKBGN
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