Rev. 1.50, 10/04, page 106 of 448
Bit Bit
Name
Initial
Value R/W
Description
17 to 12 Cause
All 0
R/W
11 to 7
Enable
All 0
R/W
6 to 2
Flag
All 0
R/W
FPU Exception Cause Field
FPU Exception Enable Field
FPU Exception Flag Field
Each time an FPU operation instruction is executed, the
FPU exception cause field is cleared to 0. When an
FPU exception occurs, the bits corresponding to FPU
exception cause field and flag field are set to 1. The
FPU exception flag field remains set to 1 until it is
cleared to 0 by software.
For bit allocations of each field, see table 6.3.
1
0
RM1
RM0
0
1
R/W
R/W
Rounding Mode
These bits select the rounding mode.
00: Round to Nearest
01: Round to Zero
10: Reserved
11: Reserved
<Big endian>
DR (2i)
FR (2i)
FR (2i+1)
8n+4
8n+7
8n
8n+3
63
0
63 32 31 0
Floating-point register
Memory area
63
0
<Little endian>
Floating-point register
Memory area
DR (2i)
FR (2i)
FR (2i+1)
4n
4m
4n+3
4m+3
63
0
63 32 31 0
DR (2i)
FR (2i+1)
FR (2i)
8n+4
8n+7
8n+3
8n
63
0
63 32 31 0
(1) SZ = 0
(2) SZ = 1, PR = 0
63
0
63
0
DR (2i)
FR (2i+1)
FR (2i)
8n
8n+3
8n+7
8n+4
63
0
63 32 31 0
(3) SZ = 1, PR = 1
63
0
*
1
,
*
2
*
2
Notes: 1. In the case of SZ = 0 and PR = 0, DR register can not be used.
2. The bit-location of DR register is used for double precision format when PR = 1.
(In the case of (2), it is used when PR is changed from 0 to 1.)
Figure 6.5 Relation between SZ Bit and Endian
Содержание SuperH SH-4A
Страница 2: ...Rev 1 50 10 04 page ii of xx ...
Страница 8: ...Rev 1 50 10 04 page viii of xx ...
Страница 116: ...Rev 1 50 10 04 page 96 of 448 ...
Страница 178: ...Rev 1 50 10 04 page 158 of 448 ...
Страница 206: ...Rev 1 50 10 04 page 186 of 448 ...
Страница 231: ...Rev 1 50 10 04 page 211 of 448 Possible Exceptions Slot illegal instruction exception ...
Страница 235: ...Rev 1 50 10 04 page 215 of 448 Possible Exceptions Slot illegal instruction exception ...
Страница 238: ...Rev 1 50 10 04 page 218 of 448 Possible Exceptions Slot illegal instruction exception ...
Страница 408: ...Rev 1 50 10 04 page 388 of 448 Possible Exceptions Inexact Not generated when FPSCR PR 1 ...
Страница 445: ...Rev 1 50 10 04 page 425 of 448 Possible Exceptions Invalid operation Overflow Underflow Inexact ...
Страница 446: ...Rev 1 50 10 04 page 426 of 448 ...
Страница 468: ...Rev 1 50 10 04 page 448 of 448 ...
Страница 471: ......
Страница 472: ...SH 4A Software Manual ...