In order for an application to be able to send data to the log view in the Diagnostics window, you need to implement the Recmt API in the application in question. For more information on using the Recmt API, see About the REcmt API.
Establish a connection between the S60 device and Device Connectivity Tool. (See Starting the Device Connectivity Tool on your PC.)
Open the Diagnostics window to monitor the activities of the application running on the S60 device. (See Introduction to Diagnostics window.)