Foot Switch with Serial Port

Question

Hello All,

 

I am working on a project(3.5) where i need to perform some operations with button Pressed of foot switch,

I am using SerialPort to Connect to the foot switch and capturing output from pinchanged event,

there are two buttons on my foot pedal, When right button is pressed my code works fine and

pinchanged event get fired But Its not working when Left button is pressed.

 

Please Help me, I am stuck here from two days.