tools/examples/basics/pwm_piezobuzzer/readme.txt

   1 This example uses a 16-bit timer for PWM, and makes a common
   2 piezo buzzer beep briefly once per second at an alternating
   3 frequency.
   4
   5 The piezo-buzzer used in this example is the PS1240, available
   6 from Adafruit Industries at:
   7
   8 http://www.adafruit.com/index.php?main_page=product_info&cPath=35&products_id=160
   9
  10 The buzzer should have one pin (either is fine) connected to P1.9
  11 on the LPC1343, and the other pin connected to GND.  CFG_PWM must also
  12 be enabled in projectconfig.h.