Instruction Manual

Appendix C: Ladder Diagram Block Reference Pointe Controller User Guide
410
* Any Input, Output, or Memory tag except 32-bit Real (F) or Bit (X). For more information, see
“Defining Input, Output, Memory tags” on page 114.
C.7.3 Extract sub-string from left (LEFT)
When used in a Ladder Diagram, the LEFT block extracts a sub-string of specified
length from the left end of a string (variable or literal) and sends the result to an
output.
Select the
tool (from the String Blocks toolbar) and click on a ladder rung to
insert the following block:
Once the block is inserted, you can double-click on it to configure it.
Functional Description
This block always passes the Enable input state (EN) through to the Enable Out
output state (ENO) without change; when EN becomes on, ENO is turned on, and
when EN becomes off, ENO is turned off.
When EN becomes on, the block function is executed: a sub-string of up to
specified Length (LEN) is extracted from the Input String (IN) and placed in the
Output String (OUT). The sub-string is extracted from the left end of IN.
For example:
IN: ‘Hello world. This is PointeControl.’
LEN: 8
OUT: ‘Hello wo’
The block function is executed every time the ladder is scanned, so long as EN
remains on. If EN becomes off, then OUT remains at its last calculated value until
EN becomes on and the block function is executed again.