Data formats, 276 programming appendix a – Omron HOME SECURITY SYSTEM - MOTION SENSOR FQM1-MMA21 User Manual

Page 299

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276

Programming

Appendix A

Data Formats

The following table shows the data formats that the FQM1 can handle.

Note Signed Binary Data

In signed binary data, the leftmost bit indicates the sign of binary 16-bit data. The value is expressed in
4-digit hexadecimal.

Positive Numbers: A value is positive or 0 if the leftmost bit is 0 (OFF). In 4-digit hexadecimal, this is
expressed as 0000 to 7FFF hex.

Data type

Data format

Decimal

4-digit

hexadecimal

Unsigned
binary

0 to
65535

0000 to FFFF

Signed
binary

0 to
–32768
0 to
+32767

8000 to 7FFF

BCD
(binary
coded dec-
imal)

0 to 9999

0000 to 9999

Single-pre-
cision
floating-
point deci-
mal

---

---

15 14 13

12 11

10

9

8

7

6

5

4

3

2

1

0

2

15

2

14

2

13

2

12

2

11

2

10

2

9

2

8

2

7

2

6

2

5

2

4

2

3

2

2

2

1

2

0

2

3

2

2

2

1

2

0

3276816384 8192 4096 2048 1024 512

256 128

64

32

16

8

4

2

1

2

3

2

2

2

1

2

0

2

3

2

2

2

1

2

0

2

3

2

2

2

1

2

0

Decimal

Hex

Binary

15 14 13

12 11

10

9

8

7

6

5

4

3

2

1

0

2

15

2

14

2

13

2

12

2

11

2

10

2

9

2

8

2

7

2

6

2

5

2

4

2

3

2

2

2

1

2

0

2

3

2

2

2

1

2

0

3276816384 8192 4096 2048 1024 512

256 128

64

32

16

8

4

2

1

2

3

2

2

2

1

2

0

2

3

2

2

2

1

2

0

2

3

2

2

2

1

2

0

Sign bit: 0: Positive, 1: Negative

Binary

Decimal

Hex

15 14 13

12 11

10

9

8

7

6

5

4

3

2

1

0

2

3

2

2

2

1

2

0

2

3

2

2

2

1

2

0

2

3

2

2

2

1

2

0

2

3

2

2

2

1

2

0

Decimal

0 to 9

0 to 9

0 to 9

0 to 9

Binary

31 30 29

23

22

21

20 19 18 17

3

2

1

0

Sign of
mantissa

Exponent

Mantissa

x 1.[Mantissa] x 2

Exponent

Sign (bit 31)

Mantissa

Exponent

Note

This format conforms to IEEE754 standards for single-precision floating-

point data and is used only with instructions that convert or calculate
floating-point data. It can be used to set or monitor from the I/O memory
Edit and Monitor Screen on the CX-Programmer. As such, users do not
need to know this format although they do need to know that the formatting
takes up two words.

1: negative or 0: positive

The 23 bits from bit 00 to bit 22 contain the mantissa,
i.e., the portion below the decimal point in 1.

@@@.....,

in binary.

The 8 bits from bit 23 to bit 30 contain the exponent.
The exponent is expressed in binary as 127 plus n in
2

n

.

Value = (

1)

Sign

Binary

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