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Rockwell Automation 1771-DA,D17716.5.13 U MNL 1771-DA ASCII I/O MODULE User Manual

Page 113

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ASCII I/O Module Tutorial

Chapter 4

4Ć39

In this demonstration, you will enter a string of data greater than the set
string length and observe how it is stored in the data table.

Retain the same initialization data: 15 character string length,
end-of-string delimiter, and left justified data.

1.

Enter: 01234567890123456789[ENTER].

Refer to the procedures in section titled “Reading Data From Your ASCII
Device” (P. 1-10).

Procedure P1

Connect the 1770ĆCB cable, and set your industrial

terminal to alphanumeric mode (check parameters)

Initialize the module by changing PLCĆ3 operation mode

3[ENTER]2[ENTER]

Procedure P2

Enter your data

Procedure P3

Connect the 1775ĆCAT cable, and set your industrial

terminal to PLCĆ3 mode

Procedure P4

Observe how the data string is stored in data table file O6.0

Results Two transfers took place (Figure 3.7). The first transfer occurred
when the string length exceeded the set string length (when you entered
the second 5) If you could have looked into the file, it would have
appeared in ASCII or in hex, respectively, as follows:

Figure 3.7

Division of Data Between Two Transfers

1st transfer

15 characters

2nd transfer

terminated by

0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9

[ENTER]

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