Single PIC16F84 audio signal generator

I'm lookng to convert a PC controlled audio signal generator into a stand-alone unit controlled by a PIC16F84. The existing unit takes it's input as a 24-bit word (3 x 8 bytes) via the PC parallel printer port. Does anyone know if it is possible to convert this unit to run with a single PIC or would i need two ?

I'm loking at take an input from a 4x4 matrix keypad (the desired frequency). The output would be to an LCD 16x2 alphanumeric display and also to the existing audio signal generator circuitry. Any help would be appreciated.

PIC16F876 (28 pin) has enough I/O pins to do what you want. It has two 8-bit ports and one 6-bit Port which are sufficient enough. Use PA (6-bit) for your LCD (in 4-bit addressing mode), PB for supplying data to signal generator and PC for 4x4 matrix keypad.
If you find that I/O are less then use PIC16F877 (40 pin) which is from same family but has more I/Os.