Drive the buzzer thru a pnp transistor as thus:

                              +5V
I/O    10k          100k      |
 ---/\/\/\/\---+---/\/\/\/\---+
               |        E_____|
               |     B |/
               +-------|\__
                        C  |
                           |
                           /
                          /
                         +-----+
                         |     | BUZ
                         +-----+
                            |
                           GND

Use a "frequency-controlled" type of
buzzer (which works like conventional
speakers), and you can generate
various frequency to your liking.

If you like I can mail you the formula
for generating melodies, like
"DO, RE, MI", etc.

Regards,
Peter Tiang
======================================

>>> NCS Products <ncs@WORLDNET.ATT.NET> 29/May/1998 09:04am >>>
I want to add sounds to a product--beeps and boops and the like.

Can I just hook a piezo speaker to a PIC output pin?
Or should I use a resistor and/or capacitor in series?