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APPENDIX
■
Using double type and long-double type
During access to data of double or long-double type, a word in either the higher bits or the lower
bits of the data is accessed. Access to double type and long-double type variables allocated in
the little-endian area does therefore not produce correct results.
Variables of the same type allocated in the little-endian area can be replaced by each other.
However, as a result of optimization, these insertions may be performed as constant insertions.
Do not allocate variables of double type and long-double type in the little-endian area.
[Erroneous example] Transfer of double-type data
The execution result of the above example is shown below. It is not correct as result of a
double-type data transfer.
■
Allocation of stacks in the little-endian area
Integrity of operation results cannot be assured if all or some stacks are allocated in the little-
endian area.
double big = 1.0; /* Big-endian area */
extern int little; /* Little-endian area */
little = big; /* Transfer of double-type data */
3f f0 00 00 00 00 00 00
00 00 f0
f0
3f
3f
00 00 00 00
00 00 00 00 00 00
(Big-endian area)
(Little-endian area)
(Correct result)
Содержание MB91150 Series
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Страница 3: ...FUJITSU LIMITED FR30 32 BIT MICROCONTROLLER MB91150 Series HARDWARE MANUAL ...
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Страница 10: ...vi ...
Страница 112: ...96 CHAPTER 3 MEMORY SPACE CPU AND CONTROL UNIT ...
Страница 174: ...158 CHAPTER 5 I O PORTS Note DDRI bit 6 is a test bit Always set the bit to 0 The value read from this bit is always 0 ...
Страница 178: ...162 CHAPTER 5 I O PORTS ...
Страница 214: ...198 CHAPTER 7 16 BIT RELOAD TIMER ...
Страница 240: ...224 CHAPTER 8 PPG TIMER ...
Страница 310: ...294 CHAPTER 13 8 10 BIT A D CONVERTER ...
Страница 318: ...302 CHAPTER 14 8 BIT D A CONVERTER ...
Страница 362: ...346 CHAPTER 15 UART ...
Страница 420: ...404 CHAPTER 19 PERIPHERAL STOP CONTROL ...
Страница 428: ...412 CHAPTER 20 CALENDAR MACROS ...
Страница 503: ...487 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Страница 510: ...494 INDEX ...
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