User`s manual

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MELSEC-Q

2 STRUCTURE AND COMBINATIONS OF PROCESS CONTROL

INSTRUCTIONS

2.2 Method for Specifying the Data in a Device

The following 4 types of data can be used by the process control instructions.

Bit data

Numeric data Integer data

Word data

Double word data

Real number data

(floating-point data)

Data that can be handled

by process control instruction

2.2.1 For bit data

Bit data is handled on a single bit basis.

The QnPHCPU uses a word device for alarm condition or selection on a single bit basis.

By specifying the bit number of the word device, you can use the 1/0 of the specified bit number

as bit data.

b15 b0

1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0

1 in each bit can be used as ON,

or 0 as OFF.

Word device

Specify the bit of the word device in the form of " Word device .Bit No.".

(Specify the bit number in hexadecimal.)

For example, specify the bit 5 (b5) of D0 as D0.5, and the bit 10 (b10) of D0 as D0.A.

However, you cannot specify the bits of the timer (T), retentive timer (ST), counter (C) and index

2.2.2 For word (16-bit) data

Word data is the 16-bit numeric data that is used for the loop tag memory bit pack contents and

operation constants, etc.

• Decimal constant....................K-32768 to K32767

• Hexadecimal constant............H0000 to HFFFF

Example) For the loop tag memory ALM (standard value setting 4000

)

0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0

ALM

4 0 0 0