MELSEC-Q Item Syntax

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Two syntax versions are available for setting up items.

 

1. Simple version:

<Area><Start address>[.Array size][Suffix]

 

2. Expanded version:

<Area><.Type><Start address>[.Array size][Suffix]

Legend: <> mandatory        [ ] optional

 

REMEMBER :

With the expanded version, a period is required between the <area> and the <type>. If the period is omitted, the syntax uses the simple version. The <type> then corresponds to the default type (for bit area BIT, for word area WORD – see table <Bereich> (Area)).
If the representation of the start address is HEX, all numbers for this area are also HEX.
The HEX / decimal numbers can be changed with the following prefixes.
Conversion of HEX -> DEC: Input of 0d (number zero + the letter d) before the decimal address
Conversion of DEC -> HEX Input of 0x (number 0 + the letter x) before the hexadecimal address
When words, double words or strings are registered in a bit area, the start address is a bit address and only possible on word boundaries (dec. 0/16/32... or hex: 0/10/20...) (e.g., Y.D10.3).
Bit arrays in bit areas are not possible.
Bit arrays in WORD areas with HEX representation, are not possible.

<Area>

 

Syntax

Orientation1

Representation of the Start address

Special Relay

SM

BIT

decimal

Special Register

SD

WORD

decimal

Input Relay

X

BIT

HEX

Output Relay

Y

BIT

HEX

Internal Relay

M

BIT

decimal

Latch Relay

L

BIT

decimal

Annunciator

F

BIT

decimal

Edge Relay

V

BIT

decimal

Link Relay

B

BIT

HEX

Data Register

D

WORD

decimal

Link Register

W

WORD

HEX

Timer Contact

TS

BIT

decimal

Timer Coil

TC

BIT

decimal

Timer Current Value

TN

WORD

decimal

Retentive Timer Contact

STS

BIT

decimal

Retentive Timer Coil

STC

BIT

decimal

Retentive Timer Current Value

STN

WORD

decimal

Counter Contact

CS

BIT

decimal

Counter Coil

CC

BIT

decimal

Counter Current Value

CN

WORD

decimal

Special Link Relay

SB

BIT

HEX

Special Link Register

SW

WORD

HEX

Step Relay

S

BIT

decimal

Direct Input

DX

BIT

HEX

Direct Output

DY

BIT

HEX

Index Register

Z

WORD

decimal

File Register

(Normal Access by block Switching)

R

WORD

decimal

File Register

(Serial No. Access)

ZR

WORD

HEX

1 BIT-oriented means that one bit is addressed for each physical address. WORD-oriented means that one word (16 bits) is addressed for each physical address.

<.Type> <,Type>

Typ

VT_Typ

Syntax

Simple Syntax

ex:Bit area

Ex: Word area

with Array in Bit area

with Array in Word area

useful

Suffixes

BIT

VT_BOOL

X

DY1

-----

D.X1.2

-----

-----

-----

BIT 1

VT_BOOL

-----

 

DY1

-----

D.1.2

-----

-----

-----

BYTE

VT_UI2

B

BYTE

-----

Y.B10

Y.BYTE10

R.B1

R.BYTE1

Y.B10.5

Y.BYTE10.5

R.B1.3

R.BYTE1.3

-----

INT

VT_I2

I

INT

Y.I10

Y.INT10

Y.I10

Y.INT10

R.I2

R.INT2

Y.I10.3

Y.INT10.3

R.I2.3

R.INT2.3

-----

WORD

VT_UI2

W

WORD

R20

Y.W10

Y.WORD10

R.W2

R.WORD2

Y.W10.3

Y.WORD10.3

R.W2.3

R.WORD2.3

-----

DOUBLE WORD

VT_UI4

D

DW

DWORD

-----

Y.D10

Y.DWORD10

R.D2

R.DWORD2

Y.D10.3

Y.DWORD10.3

R.D2.3

R.DWORD2.3

-----

DOUBLE INT

VT_I4

DI

DINT

-----

Y.DI10

Y.DINT10

R.DI2

R.DINT2

Y.DI10.3

Y.DINT10.3

R.DI2.3

R.DINT2.3

-----

REAL

VT_R4

R

REAL

-----

Y.R10

Y.REAL10

R.R2

R.REAL2

Y.R10.3

Y.REAL10.3

R.R2.3

R.REAL2.3

-----

STRING

VT_BSTR

S

STRING

-----

Y.S10.20

Y.STRING10.20

R.S2

R.STRING2.20

-----

-----

-----

1 Careful: With HEX addresses, it’s better to select the version with the X.

[.Array size]

Arrays are created to combine several units of one data type into one field.

Examples:

D20.300

For more information on arrays, see also Arrays.

[Suffix]

Suffixes can be used to represent a value in another format.

Example: D20.300KF

For more information on suffixes, see also Suffixes.