HD6413003RF Datasheet, PDF (87/715 Pages) Renesas Technology Corp – Microcontroller (MCU)

ø
RES
Address bus
RD
HWR, LWR
D₁₅ to D₀
Vector fetch
Internal
processing
Prefetch of first
program instruction
(1)
(3)
(5)
High
(2)
(4)
(6)
(1), (3)
(2), (4)
(5)
(6)
Address of reset vector: (1) = H'00000, (3) = H'00002
Start address (contents of reset vector)
Start address
First instruction of program
Note: After a reset, the wait-state controller inserts three wait states in every bus cycle.
Figure 4-3 Reset Sequence (Modes 2 and 4)
4.2.3 Interrupts after Reset
If an interrupt is accepted after a reset but before the stack pointer (SP) is initialized, 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. The first instruction of the program is
always executed immediately after the reset state ends. This instruction should initialize the stack
pointer (example: MOV.L #xx:32, SP).
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