HD6413008F RENESAS [Renesas Technology Corp], HD6413008F Datasheet - Page 114

• Manufacturer Part Number: HD6413008F
• Description: Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series
• Manufacturer: RENESAS [Renesas Technology Corp]

4. Exception Handling
4.2.3
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 exception handling. 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).
Rev.4.00 Aug. 20, 2007 Page 70 of 638
REJ09B0395-0400
φ
RES
Address bus
RD
HWR
D
(1), (3)
(2), (4)
(5)
(6)
Note: After a reset, the wait-state controller inserts three wait states in every bus cycle.
15
to D
,
LWR
0
Address of reset exception handling vector: (1) = H'000000, (3) = H'000002
Start address (contents of reset exception handling vector address)
Start address
First instruction of program
Interrupts after Reset
Figure 4.3 Reset Sequence (Modes 2 and 4)
High
(2)
(1)
Vector fetch
(4)
(3)
Internal
processing
(6)
(5)
Prefetch of first
program instruction