Mitsubishi Electric MELSEC iQ-F Series Training Manual page 116

5.4.3
32-bit data instructions and their necessities
• This section describes the concept of two words.
• This section describes the differences between a one-word instruction and two-word instruction.
• The unit of the data memory of the MELSEC iQ-R series programmable controller is one word that consists of 16 bits. Thus,
data is typically processed in units of one word at the transfer processing, comparison, and arithmetic operation.
• The MELSEC iQ-R series programmable controller can process data in units of two words (32 bits). In that case, "D" is
added at the beginning of each instruction to indicate that the instruction processes two-word data. The following shows
examples.
Instruction
Transfer MOV(P)
Comparison <, >, <=, >=, =, <>
Arithmetic operation +(P)
-(P)
*(P)
/(P)
Available range of -32768 to 32767
numerical values
Available range of digit K1 to K4
specification
• The following shows the weights of 32 bits.
b31 • • • • • • • • • • • • • • • • • • • • • • • • • • •
As the case of 16-bit data processing, the programmable controller takes the 2's complement in 32-bit data processing.
Thus, the most significant bit b31 (b15 for 16-bit data) is processed as a sign bit.
b31 • • • • • • • • • • • • • • • • • • • • • • • • • • • •
Most significant bit
(Sign bit)
1 word
16 bits
DMOV(P)
D<, D>, D<=, D>=, D=, D<>
D+(P)
D-(P)
D*(P)
D/(P)
-2147483648 to 2147483647
K1 to K8
b16 b15
0: Positive value
1: Negative value
2 words
32 bits
• • • • • • • • • • • • • • • • • • • • • • • • • • •
b0
Available range of values
-2147483648 to 0 to 2147483647
5 BASIC INSTRUCTIONS -PART 2-
5.4 Arithmetic Operation Instructions
5
b0
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