Maybe tell us which Parallax GPS you're using?
Is the convention with Software Serial that different from using the UART?
I successfully wrote a programme recently to read a GPS and store the results in an array.
I think that you have to check for Serial.available each time?
id est:
while (serial_idx < 13) // loop - capture hhmmss bytes
// GPSchar[07]..[12]
{
if(Serial.available() > 0) // ! ! !
{
GPSchar[serial_idx] = Serial.read();
serial_idx++;
}
}