Delta Electronics VFD-E manual Type, Word devices Program Steps

Appendix D How to Use PLC Function

API

Mnemonic

Operands

Function

21

SUB

P

S1, S2, D

Subtraction

Type

Bit Devices

Word devices

Program Steps

OP

X

Y

M

K

H

KnX

KnY

KnM

T

C

D SUB, SUBP: 7 steps

S1

*

*

*

*

*

*

*

*

DSUB, DSUBP: 13 steps

S2

*

*

*

*

*

*

*

*

D

*

*

*

*

*

Operands:

S1: Minuend S2: Subtrahend D: Remainder

Explanations:

1.This instruction subtracts S1 and S2 in BIN format and stores the result in D.

2.The highest bit is symbolic bit 0 (+) and 1 (-), which is suitable for algebraic subtraction.

3.Flag changes in binary subtraction In 16-bit instruction:

A.If the operation result ＝ 0, zero flag M1020 = On.

B.If the operation result ＜ -32,768, borrow flag M1021 = On.

C.If the operation result ＞ 32,767, carry flag M1022 = On.

Program Example:

In 16-bit BIN subtraction:

When X0 = On, the content in D0 will minus the content in D10 and the remainder will be stored in D20.

X0

SUB D0 D10 D20

Revision June 2008, 04EE, SW--PW V1.11/CTL V2.11 D-53