Double Signed Binary Subtract Without Carry: -L(411) - Omron SYSMAC CJ - REFERENCE MANUAL 01-2008 Reference Manual

Symbol Math Instructions
Precautions
Examples
3-11-10 DOUBLE SIGNED BINARY SUBTRACT WITHOUT CARRY: –L(411)
Purpose
Ladder Symbol
Variations
Applicable Program Areas
Name Label
Carry Flag CY
Overflow Flag OF
Underflow Flag UF
Negative Flag N
When –(410) is executed, the Error Flag will turn OFF.
If as a result of the subtraction, the content of R is 0000 hex, the Equals Flag
will turn ON.
If the subtraction results in a borrow, the Carry Flag will turn ON.
If the result of subtracting a negative number from a positive number is nega-
tive (in the range 8000 to FFFF hex), the Overflow Flag will turn ON.
If the result of subtracting a positive number from a negative number is posi-
tive (in the range 0000 to 7FFF hex), the Underflow Flag will turn ON.
If as a result of the subtraction, the content of the leftmost bit of R is 1, the
Negative Flag will turn ON.
When CIO 000000 is ON in the following example, D00110 will be subtracted
from D00100 as 4-digit signed binary values and the result will be output to
D00120.
Subtracts 8-digit (double-word) hexadecimal data and/or constants.
−
L(411)
Mi
Su
R
Variations Executed Each Cycle for ON Condition
Executed Once for Upward Differentiation
Executed Once for Downward Differentiation Not supported.
Immediate Refreshing Specification
Block program areas
OK OK
Operation
ON when the subtraction results in a borrow.
OFF in all other cases.
ON when the result of subtracting a negative number from
a positive number is in the range 8000 to FFFF hex.
OFF in all other cases.
ON when the result of subtracting a negative number from
a positive number is in the range 0000 to 7FFF hex.
OFF in all other cases.
ON when the leftmost bit of the result is 1.
OFF in all other cases.
−
Mi: Minuend word
Su: Subtrahend word
R: Result word
Step program areas Subroutines
OK
Section 3-11
–L(411)
@–L(411)
Not supported.
Interrupt tasks
OK
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