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4.3.2
Interrupts after Reset
If an interrupt is accepted after a reset and before the stack pointer (SP) is initialized, the PC and
CCR will not be saved correctly, leading to a program crash. To prevent this, all interrupt requests,
including NMI, are disabled immediately after a reset. Since the first instruction of a program is
always executed immediately after the reset state ends, make sure that this instruction initializes
the stack pointer (example: MOV.L #xx: 32, SP).
4.3.3
On-Chip Peripheral Modules after Reset is Cancelled
After a reset is cancelled, the module stop control registers (MSTPCR) are initialized, and all
modules operate in module stop mode. Therefore, the registers of on-chip peripheral modules
cannot be read from or written to. To read from and write to these registers, clear module stop
mode.
Rev. 1.00, 05/04, page 62 of 544
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