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Data file 2 – status, N7:15, T4:7.acc – Rockwell Automation 1747-PT1, D1747NP002 Hand-Held Terminal User Manual

Page 59

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Chapter 4
Data File Organization and Addressing

4–3

Typical element, word, and bit addresses are shown below:

Type

N7:15

Element

Number

File

File

Delimiter

Element

Type

T4:7.ACC

Element

Number

File

File

Delimiter

Element

Word

Delimiter

Word

Type

B3:64/15

Element

Number

File

File

Delimiter

Element

Bit

Delimiter

Bit

An element address

A word address

A bit address

The address format varies, depending on the file type. This is explained in
the following sections, beginning with file 2, the status file, and following
with files 0, 1, 3, 4, 5, 6, and 7.

Data File 2 – Status

The status file is explained in chapter 27. You can address various bits and
words as follows:

Format

Explanation

S

Status file

:

Element delimiter

S:e/b

e

Element
number

Ranges from 0 to 15 in a SLC 5/01 or fixed controller, 0-32
in a SLC 5/02. These are 1-word elements. 16 bits per
element.

/

Bit delimiter

b

Bit number

Bit location within the element. Ranges from 0 to 15.

Examples:

S:1/15

Element 1, bit 15. This is the “first pass” bit, which you can use to
initialize instructions in your program.

S:3

Element 3. The lower byte of this element is the current scan time.
The upper byte is the watchdog scan time.