Data Collection from Serial instrument

I have a process controller that returns readings in hex format pressure/flow/temp/speed/power/torque over a serial port I need a GUI to run under XP to display these values on screen. The user can enter a warning level for speed and pressure and the software will sent a halt message if its exceeded. There is also a start button that is enabled if the safety sensors of of the machine are correct correct (these sensors are returned as an 8 bit value)and allows manual start/stop There is also a need to save some setup parameters so that the process parameters can be saved. This will inclued things like Model Name, Assy operator, model serial etc I have a GUI written in C++ with source. This will give you a good idea of what I am looking for. It works fine but needs to be extended to log data The project is to extend the logging capabilities so that when the operator clicks on a button the curretly displayed parameters are logged to an excel file. The current code can be modified or else the app rewritten