Data file 5 - counters – Rockwell Automation 1747-DTAM-E,D17476.1 Data Table Access Module (DTAM) User Manual

Page 103

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SLC 500 Data Files and Logical Addressing

B-7

Publication 1747-6.1

Data File 5 - Counters

Counters are 3-word elements. Word 0 is the control word, word 1
stores the preset value, and word 2 stores the accumulator value. This
is illustrated below.

Assign counter addresses as follows:

Format

Explanation

Cf:e

C

Counter

f

File number.

Number 5 is the default file. A file
number between 10-255 can be used if
additional storage is required.

:

Element delimiter

e

Element
number

Ranges from 0 to 255. These are 3-word
elements. See the figure above.

Examples:

C5:0

Element 0, counter file 5.

Address bits and words by using the format CF:e.s/b where Cf:e is explained above, and

. is the word delimiter
s indicates subelement
/ is the bit delimiter
b indicates bit

C5:0/15
C5:0/14
C5:0/13
C5:0/12
C5:0/11
C5:0/10

C5:0.1
C5:0.2

C5:0.1/0
C5:0.2/0

Count Up Enable
Count Down Enable
Done bit
Overflow bit
Underflow bit
Update accumulator bit (HSC only)

Preset value of the counter
Accumulated value of the counter

Bit 0 of the preset value
Bit 0 of the accumulated value

CU CD

14

DN

12

O UN UA

7

6

5

nternal Use

15

13

11 10 9

Preset alue PRE

8

Accumulated alue ACC

4

0

0

1

2

Word

3

2

1

Counter Element

Addressable Bits

Addressable Words

o
o do
o

ro

dro

d or

o

r
d

d r

r o ddr

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