Delta Electronics AH500, Руководство пользователя

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C h a p t e r 3 D e v i c e s
Word: A word is composed of two consecutive bytes (i.e. 16 bits,
b15~b0). Words can be used to represent 0000~FFFF in the
hexadecimal system.
Double word: A double word is composed of two consecutive words (i.e. 32 bits,
b31~b0). Double words can be used to represent
00000000~FFFFFFFF in the hexadecimal system.
The relation among bits, nibbles, bytes, words, and double words in the binary system is
shown below.
b31 b 30 b29 b 28 b27 b26 b25 b 24 b23 b 22 b21 b20 b 19 b18 b 17 b16 b 15 b14 b 13 b12 b 11 b10 b9 b8 b7 b6 b5 b4 b3 b2 b1 b0
N B0 N B1 N B2 N B3 N B4 N B5 N B6 N B7
B Y 3 B Y 2 B Y 1 B Y 0
W 1
D W
W 0
Double word
W ord
Byte
Nib ble
Bit
2. Decimal number (DEC)

A decimal number can be used as the setting value of a timer, or the setting value of a
counter, e.g. TMR T0 K50 (K indicates that the value following it is a constant.).

A decimal number can be used as the number of an S/M/SM/T/C/D/SR/V/Z/P device,
e.g. M10 and T30.

A decimal number can be used as an operand in an applied instruction, e.g. MOV K123
D0 (K indicates that the value following it is a constant.).

Decimal numbers can be used as external input numbers, e.g. X0.0~X0.15 and X1.0~X
1.15.

Decimal number can be used as external output numbers, e.g. Y0.0~Y0.15 and
Y1.0~Y1.15.
3. Hexadecimal number (HEX)

A hexadecimal number can be used as an operand in an applied instruction, e.g. MOV
H1A2B D0 (H indicates that the value following it is a constant.).
Constant (K): A decimal number is generally preceded by K. For example, K100 represents the
decimal number 100.
Exception:
If K is used with an M/S device, a nibble device, a byte device, a word device, or a
double word device will be formed.
Example:
K1M100 represents a device composed of 4 bits, K2M100 represents a device
composed of 8 bits, K3M100 represents a device composed of 12 bit, and
K4M100 represents a device composed of 16 bits.
Constant (16#): A hexadecimal number is generally preceded by 16#. For example, the
hexadecimal number 16#100 represents the decimal number 256.
Floating-point number (F): A floating-point number is generally preceded by F. For example, the
floating-point number F3.123 represents 3.123.
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