The core Arduino based serial port code is only included in your sketch if you actually use it. For example:
Serial.println("Using Arduino supplied HardwareSerial");
So if you've copied the SerialPort folder from the zip file into your Libraries folder (So you have Arduino-1.0\libraries\SerialPort\SerialPort.h and Arduino-1.0\libraries\SerialPort\SerialPort.cpp) you can write the following code instead
SerialPort<0, 32, 256> port;
port.println("Using SerialPort class");
Just remember to do the following and you should be alright:
- Include <SerialPort.h>
- Declare new Serial port including its parameters
- Initialise (call begin()) and use the new serial port (NOT Serial)
The configuration of the serial port looks odd to anyone not familiar with C++ templates, but it's easy to explain. The first parameter inside the angle brackets is the serial port number. Unless you've got a board with more than one serial port (e.g. Arduino Mega) this will always be 0. The second parameter is the size of the receive buffer in bytes and the third is the size of the transmit buffer in bytes.
You can ignore the stuff about editing SerialPort.h. You'll only need this is you're short of flash memory at which point you can come back and ask more questions.
If you do by chance refer to both the new SerialPort and HardwareSerial in the same sketch you'll get some error messages about duplicate interrupt vectors.
Hope that helps.