Rockwell Automation 1734-485ASC POINT I/O ASCII User Manual - Manual (Page 67)

Publication 1734-UM009B-EN-P - July 2003
Using the ASCII Modules with the ControlLogix System Application Examples B-7
The ladder logic below increments a counter every 8 seconds and
then copies the accumulator value of the counter into the transaction
ID location Local:1:O.Data[1]. When the counter reaches 255, it is
automatically wrapped around to 0.
In the output table below, the data being transmitted is already inside
the data table starting at Local:1:O.Data[4] and a constant length of 9 is
in Local:1:O.Data[3]. Under normal conditions, the transmit data and
length would be loaded by the ladder program prior to incrementing
the transaction ID.