square waves (or pulse waves) 8 Hz duty cycle?

[Petr]

And here's something from me too 

Code: (Select All)

FREQ = 8

Pi2 = 8 * Atn(1)

Amplitude = .3

SampleRate = _SndRate

FRate = FREQ / SampleRate



Screen _NewImage(640, 480, 32)



Cls

Color _RGB32(255)

Locate 1

Print "Press + or - to change frequency, ESC to exit"

Locate 2

Print "Frequency: "; FREQ; " Hz"



x = 0

oldY = 240

PSet (0, 240)

ox = 0

oy = 240

Do

    duration = duration + 1

    sample = Amplitude * Sgn(Sin(Pi2 * duration * FRate))

    _SndRaw sample



    y = 240 - sample * 200

    Line (x + 1, y - 130)-(x + 1, y + 130), _RGB32(0)

    PSet (ox, oy)

    Line -(x, y), _RGB32(0, 200, 0)

    ox = x

    oy = y

    oldY = y

    x = x + .05

    If x > 639 Then

        Color _RGB32(255)

        Locate 1

        Print "Press + or - to change frequency, ESC to exit"

        Locate 2

        Print "Frequency: "; FREQ; " Hz"

        x = 0

        Line (0, y - 130)-(0, y + 130), _RGB32(0)

        PSet (0, 240)

    End If



    Do



        i$ = InKey$

        Select Case i$

            Case "+"

                FREQ = FREQ + 1

                If FREQ > 20000 Then FREQ = 20000

                FRate = FREQ / SampleRate

                Locate 2

                Print "Frequency: "; FREQ; " Hz  "



            Case "-"

                FREQ = FREQ - 1

                If FREQ < 1 Then FREQ = 1

                FRate = FREQ / SampleRate

                Locate 2

                Print "Frequency: "; FREQ; " Hz  "

        End Select



    Loop Until _SndRawLen < .1

Loop Until _KeyDown(27)

End