using PortAudio const RADIANS_PER_FRAME = 1 / 44100 * 440 * 2 * pi function test() stream = PortAudioStream() do _, output_array, frames_per_buffer, frames_already # 44100 frames / second # 440 cycles / second # 2pi radians / cycle if frames_already > 44100 0 else for frame in 1:frames_per_buffer output_array[1, frame] = sin((frames_already + frame) * RADIANS_PER_FRAME) end frames_per_buffer end end start(stream) sleep(2) close(stream) end