Chapter 16 PLC Function ApplicationsMH300
SUB
BIN subtraction
SUB
Continuous
execution type
SUBP
DSUB
Continuous
execution type
DSUBP
Flag signal: M1020 Zero flag
M1021 Borrow flag
M1022 Carry flag
Refer to the following supplementary
explanation
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Notes on operand usage: none
S1: Minuend. S2: Subtrahend. D: Difference.
Subtracts S2 from S1 using the BIN method and stores result in D.
The highest bit of any data defines the sign bit=0 indicates (positive) bit=1
indicates (negative); enables the use of algebraic subtraction operations.
Flag changes connected with subtraction.
16-bit command:
1. When calculation results are 0, the zero flag M1020 is ON.
2. When calculation results are less than -32,768, the borrow flag M1021 is ON
3. When calculation results are greater than 32,767, the carry flag M1022 is ON.
32-bit command:
1. When calculation results are 0, the zero flag M1020 is ON.
2. When calculation results are less than -
2,147,483,648, the borrow flag M1021
is ON.
3.
When calculation results are greater than 2,147,483,6477, the carry flag
M1022 is ON.
16-bit BIN subtraction: When X0=ON, subtracts the content of D10 from the
content of D0, and stores the difference in D20.