Buzzer - Buzzer story is not so simple look! Is rather particular, outputs from the ATMega8 220v ti

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Buzzer - Buzzer story is not so simple look! Is rather particular, outputs from the ATMega8 220v timer OC1A oscillator 220v timer and a pulse width is defined from the sine wave for reference is for generating a sine wave with a pulse width modulation. A low-pass filter removes the 1.8khz is a 32khz, the result of it is a pure sine wave. I realize the great sound of a sine wave of a different range (octave) as the pitch (note) with two. You can hear this song here for you. In addition to controlling the PWM output is terminated by one of the amplification of one pitch (note) that the attenuation is. - Can be a feature many wrong song. The continuous 220v timer wave of sound - Let's 220v timer nice to hear the sound for the song http://www.microsyl.com/doorbell - -PDF waveform diagram of the format of the unit sounds http://www.microsyl.com/doorbell/DoorBell.pdf /Audio.mp3 - source list // ***************************************** ********************************* // AVRDoorBell 220v timer // Version 1.0 Fev 2003 // 1.0 -> -First 220v timer Release // Sylvain Bissonnette // ******************************************** ****************************** / ******************* ************************************** / / * INCLUD 220v timer E * / / **** ************************************************** *** / #include "macros.h" // marks the standard definition used #include "iom8v.h" using the standard 220v timer definition of // ATmega8 / **************** ***************************************** / / * PROTOTYP E * / / * ************************************************** ****** / void Delay (int del); Previous definition void Timer1_CompA (void) for the input variables of // function; // Timer keompaeeo 220v timer is no input parameters void Note (unsigned char N1, unsigned char N2, unsigned char Time); // Variable pitch hamsuyong void Song (const unsigned 220v timer char * Ptr); // Song hamsuyong input variables (Melody pointer) void main (void); // Main function is not an input parameter / **************************************** ***************** / / * DEFIN E * / / ************************* ******************************** / definition are on the pitch #define TRUE 1 #define FALSE 0 // following The number // pitch frequency. # Define A2 57 / / 220hz # define A2d 60 / / 233hz # define 220v timer B2 64 / / 247hz # define C2 68 / / 262hz # define 220v timer C2d 72 / / 277hz # define 220v timer D2 76 / / 294hz # define D2d 80 / / 311hz # define E2 85 / / 330hz # define F2 90 / / 349hz # define F2d 96 / / 370hz # define G2 101 / / 392hz # define G2d 107 / / 415hz # define A3 114 / / 440hz # define A3d 120 / / 466hz # define B3 128 / / 494hz # define C3 136 / / 523hz # define C3d 144 / / 554hz # define D3 152 / / 587hz # define D3d 160 / / 622hz # define E3 170 / / 659hz # define F3 180 / / 698hz # define F3d 192 / / 740hz # define G3 202 / / 784hz # define G3d 214 / / 830hz / / The following is Sustain (sound amplitude is gradually decreased later time) of the definition is. #define N0 0 #define T1 &