Siemens SIMATIC MV440 Operating Instructions Manual page 302

Process interfacing via an automation system (PLC, PC)
10.5 Controlling the I/O interface "DI/DO"
Starting processing
Processing starts immediately upon completion of program saving.
Step
1
2
300
Input Output Description
You select a program, for example program 11.
The outputs are set as follows depending on the processing result:
Code was localized and decoded.
READ
Code matches the trained code.
MATCH
Code was not legible.
N_OK
SIMATIC MV420 / SIMATIC MV440
Operating Instructions, 04/2013, A5E02371045-06