# Retrieving the communication status of a Modbus RTU device

You can retrieve the communication status of Modbus RTU devices via status words. You can map status words to global variables in order to process them in an application program.

1. You must add Modbus RTU devices to your device configuration.

1. Open the global variables view.
2. Create a new global variable and change its data type to WORD.
3. Map the newly created variable to the desired status word. Choose from:

- Modbus RTU Master - [ID].Status Word: communication status of all slaves connected to a master
- Modbus RTU Slave - [ID].Status Word: communication status of an individual slave