Section 6 Floating-Point Unit (FPU)
Rev.1.00 Dec. 13, 2005 Page 145 of 1286
REJ09B0158-0100
•
Matrix (4
×
4)
×
matrix (4
×
4):
This operation requires the execution of four FTRV instructions.
Since an inexact exception is not detected by an FIRV instruction, the inexact exception (I) bit in
both the FPU exception cause field and flag field are always set to 1 when an FTRV instruction is
executed. Therefore, if the I bit is set in the FPU exception enable field, FPU exception handling
will be executed. It is not possible to check all data types in the registers beforehand when
executing an FTRV instruction. If the V bit is set in the FPU exception enable field, FPU
exception handling will be executed.
FRCHG: This instruction modifies banked registers. For example, when the FTRV instruction is
executed, matrix elements must be set in an array in the background bank. However, to create the
actual elements of a translation matrix, it is easier to use registers in the foreground bank. When
the LDS instruction is used on FPSCR, this instruction takes four to five cycles in order to
maintain the FPU state. With the FRCHG instruction, the FR bit in FPSCR can be changed in one
cycle.
6.6.2
Pair Single-Precision Data Transfer
In addition to the powerful new geometric operation instructions, the SH-4A also supports high-
speed data transfer instructions.
When the SZ bit is 1, the SH-4A can perform data transfer by means of pair single-precision data
transfer instructions.
•
FMOV DRm/XDm, DRn/XDRn (m, n: 0, 2, 4, 6, 8, 10, 12, 14)
•
FMOV DRm/XDm, @Rn (m: 0, 2, 4, 6, 8, 10, 12, 14; n: 0 to 15)
These instructions enable two single-precision (2
×
32-bit) data items to be transferred; that is, the
transfer performance of these instructions is doubled.
•
FSCHG
This instruction changes the value of the SZ bit in FPSCR, enabling fast switching between use
and non-use of pair single-precision data transfer.
Содержание SH7780 Series
Страница 2: ...Rev 1 00 Dec 13 2005 Page ii of l ...
Страница 28: ...Rev 1 00 Dec 13 2005 Page xxviii of l ...
Страница 50: ...Rev 1 00 Dec 13 2005 Page l of l ...
Страница 82: ...Section 1 Overview Rev 1 00 Dec 13 2005 Page 32 of 1286 REJ09B0158 0100 ...
Страница 122: ...Section 3 Instruction Set Rev 1 00 Dec 13 2005 Page 72 of 1286 REJ09B0158 0100 ...
Страница 146: ...Section 4 Pipelining Rev 1 00 Dec 13 2005 Page 96 of 1286 REJ09B0158 0100 ...
Страница 196: ...Section 6 Floating Point Unit FPU Rev 1 00 Dec 13 2005 Page 146 of 1286 REJ09B0158 0100 ...
Страница 292: ...Section 9 L Memory Rev 1 00 Dec 13 2005 Page 242 of 1286 REJ09B0158 0100 ...
Страница 450: ...Section 11 Local Bus State Controller LBSC Rev 1 00 Dec 13 2005 Page 400 of 1286 REJ09B0158 0100 ...
Страница 492: ...Section 12 DDR SDRAM Interface DDRIF Rev 1 00 Dec 13 2005 Page 442 of 1286 REJ09B0158 0100 ...
Страница 674: ...Section 15 Clock Pulse Generator CPG Rev 1 00 Dec 13 2005 Page 624 of 1286 REJ09B0158 0100 ...
Страница 692: ...Section 16 Watchdog Timer and Reset Rev 1 00 Dec 13 2005 Page 642 of 1286 REJ09B0158 0100 ...
Страница 726: ...Section 18 Timer Unit TMU Rev 1 00 Dec 13 2005 Page 676 of 1286 REJ09B0158 0100 ...
Страница 1004: ...Section 24 Multimedia Card Interface MMCIF Rev 1 00 Dec 13 2005 Page 954 of 1286 REJ09B0158 0100 ...
Страница 1032: ...Section 25 Audio Codec Interface HAC Rev 1 00 Dec 13 2005 Page 982 of 1286 REJ09B0158 0100 ...
Страница 1070: ...Section 26 Serial Sound Interface SSI Module Rev 1 00 Dec 13 2005 Page 1020 of 1286 REJ09B0158 0100 ...
Страница 1104: ...Section 27 NAND Flash Memory Controller FLCTL Rev 1 00 Dec 13 2005 Page 1054 of 1286 REJ09B0158 0100 ...
Страница 1150: ...Section 28 General Purpose I O GPIO Rev 1 00 Dec 13 2005 Page 1100 of 1286 REJ09B0158 0100 ...
Страница 1184: ...Section 29 User Break Controller UBC Rev 1 00 Dec 13 2005 Page 1134 of 1286 REJ09B0158 0100 ...
Страница 1266: ...Section 31 Electrical Characteristics Rev 1 00 Dec 13 2005 Page 1216 of 1286 REJ09B0158 0100 ...
Страница 1328: ...Appendix Rev 1 00 Dec 13 2005 Page 1278 of 1286 REJ09B0158 0100 ...
Страница 1336: ...Rev 1 00 Dec 13 2005 Page 1286 of 1286 REJ09B0158 0100 ...
Страница 1339: ......
Страница 1340: ...SH7780 Hardware Manual ...