Rockwell Automation 2706 DL40 HARDWARE USER MANUAL User Manual

Page 90

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Chapter 9
Using the Parallel Port

9 – 6

Table 9.G
Strobe line states specify type of data on the data lines

MS3

MS2

MS1

MS0

Data Type

0

0

0

0

null

0

0

0

1

D0–D15 contain the message number

0

0

1

0

D0–D15

contain the slave address

0

0

1

1

D0–D9 BDC sign bits for

(Ctrl V) variables 1–10

1

0

0

0

D0–D15 contain variable 1

1

0

0

1

D0–D15 contain variable 2

1

0

1

0

D0–D15 contain variable 3

1

0

1

1

D0–D15 contain variable 4

1

1

0

0

D0–D15 contain variable 5

1

1

0

1

D0–D15 contain variable 6

1

1

1

0

D0–D15 contain variable 7

1

1

1

1

D0–D15 contain variable 8

0

1

1

0

D0–D15 contain variable 9

0

1

1

1

D0–D15 contain variable 10

The number you assign to a variable by setting strobe lines does not
necessarily correspond to the position of the variable in a message. The
DL40 expects to see all

[CTRL][V]

variables numbered before

[CTRL][W]

variables.

Triggering Rules example:

If a message has variables positioned as follows:

[CTRL][V]

[CTRL][W]

[CTRL][V]

[CTRL][W]

[CTRL][V]

First

Position

Second

Position

Third

Position

Fourth

Position

Fifth

Position

they must be numbered:

[CTRL][V]

first position = Variable 1

[CTRL][V]

third position = Variable 2

[CTRL][V]

fifth position = Variable 3

[CTRL][W]

Second and fourth position = Variable 4 (See NOTE below)

If the variables were not numbered as shown, they would be displayed in
wrong positions and possibly corrupted.

Note:

[CTRL][V]

variables always use a (16 bit) word;

[CTRL][W]

variables do not use a full (16 bit) word.

If

[CTRL][W]

variables are ASCII (8 bit) variables,

[CTRL][W]

second

position

would be sent in the high byte of Variable 4; fourth position

would be sent in the low byte of Variable 4.

If

[CTRL][W]

s are BCD (4 bit) variables,

the [CTRL][W]

in the second

position

would be sent in the high nibble of the high byte of Variable 4;

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