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692 Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Appendix C Structured Text Programming
Example 2:
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Move ASCII characters from a SINT array into a string tag. (In a SINT
array, each element holds one character.) Stop when you reach the
carriage return.
1. Initialize Element_number to 0.
2. Count the number of elements in SINT_array (array that contains
the ASCII characters) and store the result in SINT_array_size
(DINT tag).
3. If the character at SINT_array[element_number] = 13 (decimal
value of the carriage return), then stop.
4. Set String_tag[element_number] = the character at
SINT_array[element_number].
5. Add 1 to element_number. This lets the controller check the next
character in SINT_array.
6. Set the Length member of String_tag = element_number. (This
records the number of characters in String_tag so far.)
7. If element_number = SINT_array_size, then stop. (You are at the
end of the array and it does not contain a carriage return.)
8. Go to step 3.
element_number := 0;
SIZE(SINT_array, 0, SINT_array_size);
While SINT_array[element_number] <> 13 do
String_tag.DATA[element_number] := SINT_array[element_number];
element_number := element_number + 1;
String_tag.LEN := element_number;
If element_number = SINT_array_size then
exit;
end_if;
end_while;