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Memory Tables and Bar Graphs
Section 5-2
To change the numerals or character strings displayed on the NT20, make
changes with the numeral or character-string memory table. To make changes
with the numeral or character-string memory table of the NT20, change the
contents of words by the PLC.
Note
This method is convenient when changing data has to be displayed: for exam-
ple when monitoring the contents of PLC words.
1,2,3...
1.
Use the Support Tool to allocate the numeral and character-string memory
table entries to the PLC memory.
2.
Register the memory table entries for the numerals and character strings
to be displayed when creating the screen data by using the Support Tool.
Specify “direct” as the reference method.
To display a character string, use “character display” and specify the char-
acter-string memory table entry by using the Support Tool.
To display numerals, use “numeral display” and specify the numeral mem-
ory table entry by using the Support Tool.
3.
Create a PLC program to write the contents of numerals and character
strings to be displayed on the NT20 to the PLC words.
• Important Points When Writing a Character String
If a character string to be written is smaller than “allocated word x 2”, fill up
the vacant space with normal-size spaces (20H). If unnecessary charac-
ters are left in the area, the character string will not be displayed correctly.
Application Example of the Numeral Memory Table Entries Allocated to the PLC Words
This example gives the procedure to directly display the contents of the words
allocated as the numeral memory table entries in the PLC memory. The NT20
screen display will change as the contents of the PLC word change.
• Support Tool Settings
Allocate the memory as shown below by using the Support Tool.
Numeral memory table entry #1: DM0000 (allocated words: 2 words)
Numeral memory table entry #2: DM0002 (allocated words: 1 word)
Screen numbers to be created:#1 and #2
• PLC Ladder Program
Allocated words (character-string memory table entry)
NT20
PLC
Numeral table
entry 1
Start
Start+1
Start
Start+1
Start+2
12345678
abcdef
abcdef
12345678
61 62 63 64 65 66
("a b c d e f")
Character-string
memory table
entry 4
Allocated words
(numeral table entry)
12345678
Line 1
Qty. 15289 units
Defects 23 units
Numeral memory
table entry #1
(8-digit input)
Numeral memory
table entry #2
(4-digit input)
Summary of Contents for NT20
Page 1: ...Programmable Terminal Cat No V091 E1 01 NT20 USER S MANUAL ...
Page 2: ...NT series Programmable Terminal User s Manual Produced March 2007 ...
Page 3: ...iv ...
Page 5: ...vi ...
Page 9: ...x TABLE OF CONTENTS ...
Page 15: ...xvi ...
Page 21: ...xxii EC Directives 6 ...
Page 37: ...16 Before Operating Section 1 6 ...
Page 153: ...132 Transferring the Resource Data Section 3 11 ...
Page 185: ...164 Numeral Setting Section 4 8 ...
Page 267: ...246 Key to Programs Section 6 8 ...
Page 281: ...260 Specifications Appendix A ...
Page 285: ...264 Transporting and Storing PTs Appendix C ...
Page 303: ...282 Function Restrictions Depending on the Support Tool Appendix I ...
Page 307: ...286 Index ...
Page 309: ...288 Revision History ...