Logix5000 Controllers General Instructions - SLAC Confluence

ASCII String Instructions (CONCAT, DELETE, FIND, INSERT, MID) 617Description:Arithmetic Status Flags:The MID instruction copies a group of characters from the Source andplaces the result in the Destination.• The Start position and Quantity define the characters to copy.• Unless the Source and Destination are the same tag, the Sourceremains unchanged.not affectedFault Conditions:Type Code Cause Recovery Method4 51 The LEN value of the string tag isgreater than the DATA size of thestring tag.Execution:1. Check that no instruction is writing to the LEN member of the string tag.2. In the LEN value, enter the number of characters that the stringcontains.4 56 The Start or Quantity value is invalid. 1. Check that the Start value is between 1 and the DATA size of theSource.2. Check that the Start value plus the Quantity value is less than or equalto the DATA size of the Source.Condition Relay Ladder Action Structured Text Actionprescan The rung-condition-out is set to false. No action taken.rung-condition-in is false The rung-condition-out is set to false. narung-condition-in is trueThe instruction executes.The rung-condition-out is set to true.naEnableIn is set na EnableIn is always set.The instruction executes.instruction execution The instruction copies the specified characters from a string and stores them in another string.postscan The rung-condition-out is set to false. No action taken.Example:In a baggage handling conveyor of an airport, each bag gets a barcode. Characters 9 - 17 of the bar code are the flight number anddestination airport of the bag. After the bar code is read (bag_read.EMis set) the MID instruction copies the flight number and destinationairport to the bag_flt_and_dest string.Publication 1756-RM003I-EN-P - January 2007