It displays two analog-style VU meters on two 128×64 OLED displays.
The VU meters imitate the inertia and ballistics of real analog VU meters.
It acts as a USB Audio DAC (Digital-to-Analog Converter).
Add a capacitor between the reset pin of the displays and ground, and a resistor from reset to 3.3V. The values are not critical, 0.1µF and 10kΩ work fine.
You do need some way to reset the displays, without it, it won't work.
Alternatively, you could use an IO pin from the Teensy to reset the displays, but this just "wastes" a pin.
Upload the sketch, and select the Control Surface as the audio output of your computer. Connect the output of the DAC to a pair of headphones or powered speakers, and play some music.
You should see the VU meters come to life and jump around to the music.
You can now adjust the volume using the potentiometer on pin A0, and the gain/sensitivity of the meters using the potentiometer on pin A1.
None.
constexpr uint8_t SCREEN_WIDTH = 128;
constexpr uint8_t SCREEN_HEIGHT = 64;
constexpr int8_t OLED_DC = 17;
constexpr int8_t OLED_reset = -1;
constexpr int8_t OLED_CS_L = 10;
constexpr int8_t OLED_CS_R = 18;
constexpr uint32_t SPI_Frequency = SPI_MAX_SPEED;
Adafruit_SSD1306 ssd1306Display_L {
SCREEN_WIDTH, SCREEN_HEIGHT, &SPI, OLED_DC,
OLED_reset, OLED_CS_L, SPI_Frequency,
};
Adafruit_SSD1306 ssd1306Display_R {
SCREEN_WIDTH, SCREEN_HEIGHT, &SPI, OLED_DC,
OLED_reset, OLED_CS_R, SPI_Frequency,
};
public:
MySSD1306_DisplayInterface(Adafruit_SSD1306 &display)
if (!disp.begin())
#ifdef DIGITAL_VU
disp.setRotation(1);
#endif
}
} display_L = ssd1306Display_L, display_R = ssd1306Display_R;
AudioInputUSB audioInputUSB;
AudioMixer4 mixer_L;
AudioAnalyzeRMS rms_L;
AudioMixer4 mixer_R;
AudioAnalyzeRMS rms_R;
AudioOutputI2S audioOutputI2S;
AudioConnection patchCord1(audioInputUSB, 0, mixer_L, 0);
AudioConnection patchCord2(audioInputUSB, 0, rms_L, 0);
AudioConnection patchCord3(audioInputUSB, 1, mixer_R, 0);
AudioConnection patchCord4(audioInputUSB, 1, rms_R, 0);
AudioConnection patchCord5(mixer_L, 0, audioOutputI2S, 0);
AudioConnection patchCord6(mixer_R, 0, audioOutputI2S, 1);
#ifdef DIGITAL_VU
#else
display_L,
vu_L,
{63, 63},
63,
-140 * PI / 180,
100 * PI / 180,
WHITE,
};
display_R, vu_R, {63, 63}, 63, -140 * PI / 180, 100 * PI / 180, WHITE,
};
#endif
constexpr float maxGain = 5;
FilteredAnalog<> gainKnob = A1;
void setup() {
AudioMemory(8);
FilteredAnalog<>::setupADC();
display_L.begin();
display_R.begin();
}
void loop() {
const unsigned long frametime = 1'000'000 /
MAX_FPS;
static unsigned long previousFrameTime = micros();
if (micros() - previousFrameTime >= frametime) {
previousFrameTime += frametime;
Updatable<AudioVU>::updateAll();
Updatable<Potentiometer>::updateAll();
}
if (gainKnob.update()) {
float gain = gainKnob.getFloatValue() * maxGain;
vu_L.setGain(gain);
vu_R.setGain(gain);
}
}
The main header file that includes all Control-Surface header files.
Control_Surface_ & Control_Surface
A predefined instance of the Control Surface to use in the Arduino sketches.
constexpr uint8_t MAX_FPS
The maximum frame rate of the displays.
A VU meter that reads from an Audio stream using the Analyzer class.
void updateDisplays()
Clear, draw and display all displays that contain display elements that have changed.
virtual void begin()
Initialize the display.
Displays a MCU level meter.
static MovingCoilBallistics noOvershoot(float Tsfactor=1.0)
static MovingCoilBallistics responsiveVU(float Tsfactor=2.0)
This class creates a mapping between the Adafruit_SSD1306 display driver and the general display inte...
void drawBackground() override=0
Draw a custom background.
A class for controlling the volume of AudioMixer4 objects using a potentiometer.
#define FATAL_ERROR(msg, errc)
Print the error message and error code, and stop the execution.