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WindO/I-NV2 User’s Manual 2-3

1 WindO/I-NV2 Specifications

WindO/I-NV2 Features & Basic Operations

Example: Data handling

float32

Data is handled as a 32-bit floating-point real number. The number of significant digits is 6 digits. The

floating-point type data format conforms to the IEEE (The Institute of Electrical and Electronics Engineers)

standard for the single precision storage format as explained next.

Single precision floating-point values in IEEE 754 (32 bits)

Single precision floating-point values in IEEE 754 are expressed with a total of 32 bits (2 words) using 1 bit

for the sign s, 8 bits for the exponent e, and 23 bits for the significand f. The sign bit indicates the sign of

the expressed value (positive or negative). The exponent is an 8 bit signed integer with a value from -128

to 127.

Example:

If all bits are 0, the value is “0”.

Data type Data handling

s e (exponent) [bit 30 to 23]

bit

f (significand) [bit 22 to 0]

Represents after the decimal of 1.xxx+127

Sign bit (0: positive, 1: negative)

bit

se f

01111101 10000000000000000000000

1.1×2

The internal representation of float32 is described here, but the data for float32 (floating-point real

numbers) is handled with a special bit configuration, so do not directly access the bits.

Data type Storing 0FFF (hex) in LDR10 Storing FFFF (hex) in LDR10

BIN16 (+)

0FFF (hex) is handled as 4095 (dec). FFFF (hex) is handled as 65535 (dec).

BIN16 (+/-)

0FFF (hex) is handled as 4095 (dec). Sign bit is 1, so FFFF (hex) is two’s complement,

handled as -1 (dec).

Data type

Storing 0FFF (hex) in LDR10, FFFF (hex) in

LDR11

Storing FFFF (hex) in LDR10, FFFF (hex) in

LDR11

BIN32 (+)

0FFFFFFF (hex) is handled as 268435455 (dec). FFFFFFFF (hex) is handled as 4294967295 (dec).

BIN32 (+/-)

The sign bit is 0, so the positive number 0FFFFFFF

(hex) is handled as 268435455 (dec).

Sign bit is 1, so two’s complement of the negative

number FFFFFFFF (hex), handled as -1 (dec).

bit

15 0

0FFF (Hex)

LDR10

0000111111111111

bit

15 0

FFFF (Hex)

LDR10

1111111111111111

bit

15 0

0FFF (Hex)

LDR10

1111111111110000

bit

15 0

FFFF (Hex)

LDR10

1111111111111111

−

bit

LDR11 LDR10

00001111111111111111111111111111

0FFFFFFF (Hex)

bit

LDR11 LDR10

1111111111111111111111111111

FFFFFFFF (Hex)

1111

bit

LDR11 LDR10

00001111111111111111111111111111

0FFFFFFF (Hex)

bit

LDR11 LDR10

11111111111111111111111111111111

FFFFFFFF (Hex)

−

1 2 ... 28 29 30 31 32 33 34 35 36 37 38 ... 143 144

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Idec High Performance Series Manuel d'utilisateur Page 33

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