Omron NT620C, Operation Manual

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5-2 Section Memory Tables and Graphs
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5-2 Memory Tables and Graphs
Displaying and Referencing Character-String Memory Table Contents
Since character-string memory tables can be allocated to words in the PC, the
PC can write data to the character-string memory tables, and initial values can be
set when creating the screen data.
During operation, automatic updating is performed to ensure that the currently
displayed NT620S/620C character-string memory table contents and PC word
contents always match each other.
There are two methods for referencing character-string memory tables used for
character-string display, as follows:
- Direct specification
- Indirect specification
Reference Only direct specification can be used as the reference method for character-
string memory tables used for character-string settings.
S
Direct specification
Direct specification is a method of specification in which the contents of dis-
played memory tables are directly correlated with the contents of the allocated
words.
Direct
specification
Character-string
memory table 51
Allocated word
(character-string memory table 51)
NT620S/620C PC
a b c d
6 1 6 2
6 3 6 4 a b c d
DM0100
S
Indirect specification
In indirect specification, even if the displayed data is a character-string, the dis-
play is correlated with a numeral memory table. The contents (numerical val-
ue) of this numeral memory table are regarded as a character-string memory
table number and the contents of the table with this number are displayed.
A combined total 50 of numeral displays and character-string displays can be
specified on one screen by using indirect specification.
Indirect
specification
Numeral memory
table 20
Allocated word
(numeral memory table 20)
NT620S/620C PC
a b c d 0 0 5 1 0 0 5 1
DM0000
Character-string
memory table 51
Allocated word
(character-string memory table 51)
6 1 6 2
6 3 6 4 a b c d
DM0100
This specification method is a little complex, but it allows the display to be
changed more easily according to the circumstances. In the example above, if 1