yes the invert? PIC to PIC a 1 is a 1 or a 0 is a 0 but the max chip turns input 1 from your pic in to an output o so you have to invert a 1 to 0 and a 0 to 1. Hock it up to your PC RS232 port you should get something anyway. I have used Pic16f628 and it works fine I only us MPLAB MPASM when I'm programming PIC you can do a lot and have more control of your PIC.