Although 9600 is not really fast, it will probably not be the cause of the response delay. Your post is unfortunately lacking a bit of detail.
- In your previous topic What is the com port of serial port for Bluetooth for Raspberry Pi you were trying to get Bluetooth working with a Raspberry Pi. Is the Pi still involved? If yes, is it the PC that you mention? Or is the Pi the device that the PC is communicating with? Or is the Pi out of the picture in which case it will be useful to know what the PC is communicating with?
I suggest that you give a good description of your project; please also indicate at which side your Processing application is running and what is running on the other side. - What kind of messages are you sending? At 9600, one byte takes approximately 1 millisecond to transfer. If you’re transferring the content of a book, it will indeed take time.
- Both sides of the communication channel can slow down communication if you don’t code it correctly (e.g. using some form of delay and other stuff). I suggest that you post the code for the sides of the communication channel that involve code (just in case, please don’t forget to use code tags using the </> button above the composer window on the forum).