Rockwell Automation 1734-485ASC POINT I/O ASCII User Manual - Manual (Page 64)

Publication 1734-UM009B-EN-P - July 2003
B-4 Using the ASCII Modules with the ControlLogix System Application Examples
Reading Data from the ASCII Modules into ControlLogix
For this example, the advanced mapping feature in RSNetWorx for
DeviceNet was used to separate the header bytes into their own data
locations. The diagram below illustrates that the transaction ID is in
Local:1:I.Data[0], the status byte is in Local:1:I.Data[1], and the length
is in Local:1:I.Data[3]. The ASCII data starts in Local:1:I.Data[4].