Data received from external board should visible in Simulink Display?

I am using Matlab 2010, In S-function builder, When i receive data from external device (board), it should display in the Simulation Display... I should use simple C coding which should read a text or excel file, and display in simulink display. I should use s-function builder... Can anyone help for the c-coding involved for this project.

Thank you answers will be appreciated.