how to open serial connection in matlab?

i need to send and receive some information using rs232 using proteus and matlab but it don't work . i use instruction in the help?

[Walter Roberson]

What code did you use, and what did you observe? Are you using true serial, or a serial-over-USB ?

[Hasan alomari]

i used simulation , and for coding PIC C ..

[Walter Roberson]

Do you mean that you used Simulink, and the Serial block, and used Simulink Coder to generate code for the PIC?

[Hasan alomari]

no i dont use simulink i meant simulation program which is proteus and not the other thing