In this archive is included an example code in proton basic compiler how to implement PWM using interrupt.It is used for regulating light intensity of led diode depending on light ambient.When the light is low led diode is full powered and light intensity of LED falling down as ambient light rising. -In this archive　is included an example code in proton basic compiler how to implement PWM using interrupt.It is used for regulating light intensity of led diode depending on light ambient.When the light is low led diode is full powered and light intensity of LED falling down as ambient light rising.