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2.2.3
In the case of double word (32-bit) data
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Double word data is 32-bit numeric data.
• Decimal constant......................K-2147483648 to K2147483647
• Hexadecimal constant..............H00000000 to HFFFFFFFF
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When using double word data, specify the word device to be used in the lower-order 16 bits.
The 32-bit data is stored into the (specified word device number) and ((specified word device number) + 1).
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Example) When D10 is specified for double word data, D10 and D11 are used.
2.2.4
D11
D10
(BW1)H
(BW1)L
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In the case of real number data (floating-point) data
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The data required for operations and the operation results are 32-bit floating-point data.
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Floating-point data is displayed as follows using 2 word devices.
1. [Fixed-point part] × 2 [Exponent part]
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The bit configuration when the floating-point data is expressed internally and its meaning are as follows.
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b31
b30
to
b23
b22
to
b16
b15
b23 to b30
Exponent
to
b0
b0 to b22
Mantissa
• Fixed-point part sign This shows the fixed-point part sign in b31.
0: Positive
1: Negative
• Exponent part This shows the 2n's n and b23 to b30.
The n from b23 to b30's BIN value is as follows.
b23 to b30
n
FFH
FEH FDH
Non-numeric
127
data
126
81H
2
80H
1
7FH
0
7EH
-1
02H
01H
00H
Non-numeric
-125 -126
data
• Fixed-point part This shows the value of XXXXXX... in the 23 bits, b0 to b22, when 1.XXX XXX... is represented in binary.
• The real number setting range is 0, ± 2-126  |value| < ± 2128.
• To represent 0, set 0 in all of b0 to b31.
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2.2 How to Specify Data in Devices
2.2.3
In the case of double word (32-bit) data
b31
Sign