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Data files 0 and 1 – outputs and inputs, As the slot number and, Slot and word), taken together – Rockwell Automation 1747-PT1, D1747NP002 Hand-Held Terminal User Manual

Page 60

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Chapter 4
Data File Organization and Addressing

4–4

Data Files 0 and 1 – Outputs and Inputs

Bits in file 0 are used to represent external outputs. Bits in file 1 are used to
represent external inputs. In most cases, a single 16-bit word in these files
will correspond to a slot location in your controller, with bit numbers
corresponding to input or output terminal numbers. Unused bits of the word
are not available for use.

I/O Addressing for a Controller with Fixed I/O: In the figure below, a
fixed I/O controller has 24 inputs and 16 outputs. An expansion rack has
been added. Slot 1 of the rack contains a module having 6 inputs and 6
outputs. Slot 2 contains a module having 8 outputs.

The figure shows how these outputs and inputs are arranged in data files 0
and 1. For these files, the element size is always 1 word.

The table on the following page explains the addressing format for outputs
and inputs. Note that the format specifies

e

as the slot number and

s

as the

word number. When you are dealing with file instructions, refer to the
element as

e.s

(slot and word), taken together.

Slot Numbers

Data File 0 – Output Image

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

X

X

INVALID

INVALID

Slot 0 outputs (0–15)

Slot 1 outputs (0–5)

Slot 2 outputs (0–7)

Data File 1 – Input Image

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

X

INVALID

INVALID

Slot 0 inputs (0–15)

Slot 0 inputs (16–23)

Slot 1 inputs (0–5)

X

O:0

O:1

O:2

I:0

I:0.1

I:1

0
1
2

24

6

None

16

6
8

Slot

Inputs Outputs

I/O

I/O

I/O

0

1

2

Fixed I/O

Controller

Expansion

rack

X

See Addressing “Examples,” next page.

X