Renesas SH7264 Doll User Manual


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Section 3 Floating-Point Unit (FPU)
Page 102 of 2108 R01UH0134EJ0400 Rev. 4.00
Sep 24, 2014
SH7262 Group, SH7264 Group
3.3.2 Floating-Point Status/Control Register (FPSCR)
FPSCR is a 32-bit register that controls floating-point instructions, sets FPU exceptions, and
selects the rounding mode.
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
0
0000000000000100
R R R R R R R R R R/W R R/W R/W R R/W R/W
0000000000000001
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W
Bit:
Initial value:
R/W:
Bit:
Initial value:
R/W:
- - - - - - - - - QIS - SZ PR DN Cause
Cause Enable Flag RM1 RM0
Bit Bit Name
Initial
Value R/W
Description
31 to 23 All 0 R Reserved
These bits are always read as 0. The write value should
always be 0.
22 QIS 0 R/W Nonnunerical Processing Mode
0: Processes qNaN or  as such
1: Treats qNaN or  as the same as sNaN (valid only
when FPSCR.Enable.V = 1)
21 0 R Reserved
This bit is always read as 0. The write value should
always be 0.
20 SZ 0 R/W Transfer Size Mode
0: Data size of FMOV instruction is 32-bits
1: Data size of FMOV instruction is a 32-bit register pair
(64 bits)
19 PR 0 R/W Precision Mode
0: Floating-point instructions are executed as single-
precision operations
1: Floating-point instructions are executed as double-
precision operations (graphics support instructions
are undefined)
18 DN 1 R Denormalization Mode (Always fixed to 1 in SH2A-
FPU)
1: Denormalized number is treated as zero