3. Exception Handling
Rev.3.00 Jul. 19, 2007 page 72 of 532
REJ09B0397-0300
Figure 3.1 shows the reset sequence.
Vector fetch
Internal
address bus
φ
Internal read
signal
Internal write
signal
Internal data
bus (16-bit)
RES
Internal
processing
Program initial
instruction prefetch
(1) Reset exception handling vector address (H'0000)
(2) Program start address
(3) First instruction of program
(2)
(3)
(2)
Reset cleared
(1)
Figure 3.1 Reset Sequence
3.2.3 Interrupt
Immediately after Reset
After a reset, if an interrupt were to be accepted before the stack pointer (SP: R7) was initialized,
PC and CCR would not be pushed onto the stack correctly, resulting in program runaway. To
prevent this, immediately after reset exception handling all interrupts are masked. For this reason,
the initial program instruction is always executed immediately after a reset. This instruction
should initialize the stack pointer (e.g. MOV.W #xx: 16, SP).
Содержание F-ZTAT H8 Series
Страница 6: ...Rev 3 00 Jul 19 2007 page iv of xxiv REJ09B0397 0300...
Страница 194: ...7 RAM Rev 3 00 Jul 19 2007 page 168 of 532 REJ09B0397 0300...
Страница 234: ...8 I O Ports Rev 3 00 Jul 19 2007 page 208 of 532 REJ09B0397 0300...
Страница 274: ...9 Timers Rev 3 00 Jul 19 2007 page 248 of 532 REJ09B0397 0300...
Страница 352: ...12 A D Converter Rev 3 00 Jul 19 2007 page 326 of 532 REJ09B0397 0300...
Страница 466: ...16 Electrical Characteristics H8 3854 Group Rev 3 00 Jul 19 2007 page 440 of 532 REJ09B0397 0300...
Страница 561: ......