beautypg.com

Texas Instruments TMS320C67X/C67X+ DSP User Manual

Page 50

background image

Control Register File Extensions

CPU Data Paths and Control

2-24

SPRU733

Figure 2−14. Floating-Point Adder Configuration Register (FADCR)

31

27 26

25

24

23

22

21

20

19

18

17

16

Reserved

RMODE

UNDER

INEX

OVER

INFO

INVAL

DEN2

DEN1

NAN2

NAN1

R-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

15

11 10

9

8

7

6

5

4

3

2

1

0

Reserved

RMODE

UNDER

INEX

OVER

INFO

INVAL

DEN2

DEN1

NAN2

NAN1

R-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

R/W-0

Legend: R = Readable by the MVC instruction; W = Writeable by the MVC instruction; -n = value after reset

Table 2−14. Floating-Point Adder Configuration Register (FADCR)

Field Descriptions

Bit

Field

Value Description

31−27 Reserved

0

Reserved. The reserved bit location is always read as 0. A value written to this
field has no effect.

26−25 RMODE

0−3h

Rounding mode select for .L2.

0

Round toward nearest representable floating-point number

1h

Round toward 0 (truncate)

2h

Round toward infinity (round up)

3h

Round toward negative infinity (round down)

24

UNDER

Result underflow status for .L2.

0

Result does not underflow.

1

Result underflows.

23

INEX

Inexact results status for .L2.

0

1

Result differs from what would have been computed had the exponent range
and precision been unbounded; never set with INVAL.

22

OVER

Result overflow status for .L2.

0

Result does not overflow.

1

Result overflows.

21

INFO

Signed infinity for .L2.

0

Result is not signed infinity.

1

Result is signed infinity.