Hello,
Complete noobie here with Arduino and the whole serial communication concept on the PC.
I have a desktop app that has the ability to connect to a specified COM port and send data via that port to whatever other device is connected to it, in which case I have Arduino Leonardo connected to this COM port.
The desktop app seems to connect to the COM port just fine and I can monitor data going out of it. However when I open the Arduino IDE and attempt to monitor the incoming data via its "Serial Monitor", I'm getting (Port Busy) error.
I'm assuming this is a normal behavior since that port is now taken up by the constant stream of data that is coming from my desktop app, but how do I monitor what the Arduino is picking up, processing via my code and outputting back into the COM port, without the ability to use the Serial Monitor int he IDE?
Do I need an actual LCD display connected to the Arduino itself, or is there a way to still monitor Arduino's output on the desktop?
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If this helps, the idea behind a project is a joystick.
I have built a joystick that relies on the load cells for the X/Y rather than the potentiometers or hall effect sensors. The harder I pull on the stick the more force I exert on the load cell, the more deflection I get in the Windows joystick values, without actual physical movement of the stick itself.
Everything is working fine but I want another layer of control on top of it.
I want to bring in a telemetry from my flight sim, looking specifically at the speed of the aircraft.
Speed of the aircraft will govern the extreme values for my joystick in Arduino code as well as the dampening effect in the code.
This way, the slower the aircraft is moving based on the telemetry, the more dampening I can have, and have the joystick feel more "mushy" in response.
The faster the aircraft is moving, the tighter the response becomes, but the extreme values for the joystick's X/Y will move out, so it takes more force from the load cell to get to the end of the joystick's "travel".
This is essentially an attempt to somewhat replicate a force-feedback joystick without any moving parts in it. 
Any help would be greatly appreciated.